Motivating Green Knowledge Behavior by Mindfulness Leadership in Engineering Design: The Role of Moral Identity

Abstract

The green behaviors of engineering project designers can improve the green performance of engineering projects. Moral factors are likely to influence designers’ behavior related to green design. Therefore, this study takes mindfulness leadership as a new antecedent of green behavior and explores how mindfulness leadership influences the green behaviors of designers. Based on social cognitive theory, this study proposes that mindfulness leadership stimulates the designers to exhibit green behaviors. Then, this study used a survey design and adopted partial least squares structural equation modeling to examine the hypotheses. The results indicate that mindfulness leadership is positively associated with green voice behavior (β = 0.313), green knowledge-sharing behavior (β = 0.281), and green helping behavior (β = 0.353). Moreover, moral identity mediates the main effect (β_a = 0.131, β_b = 0.147, β_c = 0.169). These quantitative findings substantiate that mindfulness leadership can effectively motivate designers to provide eco-conscious solutions, share sustainability knowledge, and collaborate on green improvements. The study equips project managers with evidence-based strategies to cultivate moral identity and leadership practices that systematically enhance environmental performance in engineering design contexts.

1. Introduction

Environmental degradation has become a significant concern in the engineering industry [1,2]. The green behaviors of engineering project designers have been the most important environmental factor on engineering projects, as they determine green development agendas and fulfill major obligations. Specifically, this study characterizes such behavior as a deliberate endeavor to recognize and mitigate negative environmental effects to benefit the ecological environment [3]. Given their key roles in the project lifecycle, engineering project designers usually translate professional project requirements and developmental ideas into practical applications [4]. For instance, during the project design phases, the designers incorporate green principles (e.g., optimizing material selection, promoting energy conservation, and enhancing recycling practices) into their design drawings. These decisions can have a profound environmental footprint on engineering projects throughout the project lifecycle [5,6]. Thus, engineering project designers play an important role in advancing sustainability within the engineering industry, and their commitment to green practices is essential for enhancing the environmental performance of engineering project designs. However, engineering project designers may face a moral dilemma resulting from the persistent tensions between technical feasibility (e.g., material specifications), economic constraints (e.g., budget optimization), and ecological accountability [7]. This will cause a moral conflict between their moral identity, which is manifested by personal environmental values, and economic maximization. However, there is a limited understanding of how leadership interventions can resolve these tensions to foster environmentally responsible decisions. Specifically, mindfulness leadership is characterized by adaptive awareness, conflict diffusion, and dynamic responses to ethical–technical trade-offs. The role of this leadership in mitigating ethical identity conflicts and enabling designers to prioritize green practices remains underexplored.

Some traditional leadership practices, such as ethical leadership [8], responsible leadership [9], and other green-specific leadership practices, including green servant leadership [10] and green transformational leadership [11], have been emphasized to enable green outcomes among employees. These studies have offered valuable perspectives to enhance our comprehension of how those leadership practices influence employee green behavior in a stable or routine landscape. In contrast, mindfulness leadership, using mindful processes to work with uncertainty and embrace change, has aroused extensive research in a complicated and dynamic project environment. For example, mindful leaders have critical skills to judge how to address exceptional circumstances [12]. According to Winch (2010) [13], project management is inherently a problem of information. As a result, mindful leaders should also capture key clues in a timely way to cope with the increasing uncertainty and complexity of environmental issues during design phases. Additionally, the focus of mindfulness leadership is on the current state and environment, which can enable their employees to concentrate on the changing environment rather than other situations [14]. As a consequence, mindfulness leadership has a significant role in motivating engineering project designers to exhibit green behavior.

While existing literature has extensively explored the impact of leadership on employee green behavior through diverse mechanisms, such as green human resource management [15], green work climate [9], and green organizational support [16], the moral cognitive underpinnings of this relationship remain under-examined. This oversight is particularly critical given that employee green behaviors are inherently moral, involving trade-offs between economic maximization and social welfare [17]. Accordingly, social cognitive theory provides a novel mediation mechanism linking mindfulness leadership to green behaviors among engineering project designers. Based on social cognitive theory, identity is the key to employee behaviors [18]. Specifically, leaders describe moral expectations to construct the moral cognition of employees and then influence employees’ behaviors. Mindfulness leadership, characterized by strong environmental awareness and moral clarity, may serve as a catalyst for shaping employees’ moral cognition [14]. Although moral identity is malleable and can change depending on the surrounding environment [19], mindful leaders convey clear information grasped from the changing environment to value moral traits and principles, and then motivate moral identity. In turn, employees are more likely to internalize the moral characteristics into their self-schema, leading to the development of environmentally conscious identities focused on prioritizing green environmental stewardship, thereby increasing the likelihood of green behavioral outcomes [20]. Hence, this study proposes that moral identity plays a mediating role between mindfulness leadership and the green behavior of engineering project designers.

Overall, this study aims to investigate how mindfulness leadership motivates green behavior among engineering project designers through the mediating moral identity. The study advances engineering project management scholarship through three key contributions. Firstly, departing from conventional leadership studies in stable environments, we pioneer the exploration of mindfulness leadership in dynamic project contexts characterized by temporal constraints, strict deadlines, and operational uncertainties. Our findings unfold an effective organizational intervention for cultivating green practices within engineering project design organizations.

Secondly, building on the existing view of engineering project organizations as knowledge-intensive systems [21,22,23], we operationalize designers’ green behavior through a tripartite conceptual framework: (1) green voice behavior, (2) green knowledge-sharing, and (3) green helping behaviors. This multidimensional construct offers a different perspective to analyze how designers perceive and respond to mindfulness leadership initiatives. Thirdly, our mediation analysis reveals moral identity as a critical psychological mechanism linking leadership practices and environmental stewardship, a theoretical connection previously unexamined in project management literature. Thus, this study provides a theoretical and practical foundation for better understanding green behaviors in engineering project design organizations.

2. Literature Review and Hypotheses Development

2.1. Green Behaviors in Engineering Project Design Organizations

Facing the increasingly environmental challenges, engineering project design organizations should execute green design principles to address ecological concerns [4,6,24]. This necessitates an examination of three environmentally oriented collaborative behaviors within organizations—green voice behavior, green knowledge-sharing behavior, and green helping behavior—and each of them contributes uniquely to organizational sustainability efforts. First, voice behavior refers to employees’ work-related behavioral responses, including talking about or raising innovative ideas at work [25]. This study extends the definition of voice behavior to environmental advocacy. It involves proactively proposing innovative green practices, challenging outdated procedures, and advocating for sustainable alternatives, even in the face of dissent [26,27]. Such green behavior encourages engineering project designers to embrace the principles of environmental sustainability and actively share ideas and suggestions for environmentally friendly alternatives, thereby fostering the organization’s cohesion and competitiveness [27,28]. Specifically, the engineering project design reflects the collective collaborative wisdom of all members of the design team [29]. To enhance design quality and minimize environmental impact, it is imperative for designers within the team to proactively articulate their innovative ideas, suggestions, and feedback on environmental concerns.

Secondly, as a specific form of bidirectional knowledge exchange [30], green knowledge sharing entails the voluntary dissemination of environmental expertise within an organization [26]. With growing environmental pressures, this collaborative practice is critical to improving environmental performance [31]. As manifestations of organizational eco-consciousness, this strategy institutionalizes sustainability principles by cultivating collective environmental accountability through collaborative learning and shared stewardship of environmental objectives [32,33]. Shafait and Huang (2024) highlighted that the exchange and absorption of environmental knowledge enhance organization members’ capacity for addressing environmental challenges [34]. Systemic knowledge integration transforms abstract green concepts into actionable solutions, driving green innovation and circular practices [35,36,37,38]. As cross-functional project teams, engineering design organizations integrate diverse and dense knowledge, experience, and innovation. Therefore, green knowledge-sharing behaviors among designers will empower engineering project design organizations to address sustainability challenges through integrating expertise collectively [22].

Additionally, green helping behavior, as voluntary assistance focused on environmental objectives, encompasses both collaborative problem solving for environmentally friendly outcomes and resource sharing among colleagues [26]. It operationalizes sustainability principles through peer-to-peer support, directly translating environmental commitments into tangible workplace actions. The intricate task interdependence within design teams necessitates heightened interdisciplinary collaboration for the successful development of environmentally sustainable engineering projects [39]. Consequently, designers ought to recognize the unique dynamics within the team, support one another, and collectively invest efforts in addressing technical and environmental challenges in green design to achieve successful outcomes [40,41]. Despite the contribution of these three environmentally oriented collaborative behaviors in engineering project design organizations, their antecedents have still been overlooked.

2.2. Mindfulness Leadership and Green Behaviors

In engineering project design contexts, green-oriented behaviors constitute strategic organizational responses to ecological imperatives. Leadership is an important factor in achieving sustainable design outcomes. Mindfulness leadership, as a new leadership style, has attracted more and more attention from scholars. As a paradigmatic management intervention, mindfulness leadership is defined as a cognitive process in which the leaders focus on the emergent organizational realities with an open, nonjudgmental attitude, maintaining a clear awareness of internal and external states, events, and experiences [42,43]. Prior research delineates some synergistic pathways through which mindfulness leadership activates these behaviors. Through daily enactment of circular environmental principles, mindful leaders institutionalize transcendent environmental values that employees assimilate via social learning processes [44,45]. According to Kumar et al. (2022), mindfulness leadership actively promoted pro-environmental behavior through transcendent values [46] and connectedness to nature [47]. Mindful leaders who demonstrate mindfulness in evaluating material sustainability or energy efficiency are more likely to encourage employees to propose alternative green solutions, even if these suggestions run counter to traditional practices. Small et al. (2021) argued that mindfulness leadership is manifested in proactive and sustained awareness of environmental changes and systematic integration of information [48]. Mindful leaders demonstrate systematic environmental scanning capabilities, such as proactively identifying material flow inefficiencies through real-time feedback on life cycle assessment metrics [48] and transparent disclosure of design decision externalities [46]. Schuh et al. (2019) considered that mindful leaders can keenly recognize the urgency of environmental issues, thus emphasizing moral and environmental responsibilities in decision making and demonstrating concern for sustainability issues through open communication [49]. Moreover, mindfulness leadership tries to provide resource support for designers to cope with environmental challenges [47,50]. Engineering project designers have to face the status quo to promote project sustainability, which often comes with a certain level of pressure. In this case, mindful leaders can frame sustainability challenges as innovation opportunities and mitigate change resistance through empathetic conflict mediation. Therefore, mindfulness leadership is beneficial for cultivating designers’ environmental awareness and alleviating their stress in coping with environmental challenges, ultimately promoting their green behavior.

Additionally, extensive research has shown that mindfulness leadership has a significant positive impact on employees’ positive work outcomes in the workplace. Doornich and Lynch (2024) indicated that some organizations use mindfulness manifested by keen attention, clear insight, and high authenticity to influence employee behavior [51]. For example, stress reduction and performance improvement [52,53]. Since social interaction is at the core of organizational phenomena [54], especially in knowledge-intensive engineering project design organizations, the social construction role of mindfulness leadership is thus underscored in the effects on employee behaviors [55,56]. Kao et al. (2021) considered that mindful leaders lead to positive organizational outcomes through their own behavioral modeling and resource transfer [57]. For example, they help employees reduce stress and negative emotions by setting a positive example for coping with stress through social modeling, providing emotional support, clear task guidance, and resource allocation [58,59]. Furthermore, they cultivate high-quality communication between leaders and members by creating a more supportive and participatory work environment [60].

Specifically, mindfulness leadership, characterized by non-judgmental awareness, present-moment focus, and ethical reflection, leads to improved accurate self-awareness, openness to accepting self-relevant information from the external environment and the promotion of an organizational climate in which people express their opinions. By improving communication in the workplace, mindfulness leadership creates an interpersonally friendly and psychologically safe environment that reduces interpersonal stress and allows employees to feel empowered to express innovative and potentially disruptive ideas about sustainability. By leading by example in moral decision making and prioritizing environmental responsibility, mindfulness leadership communicates the importance of challenging the status quo to achieve ecological goals. For instance, leaders on engineering design teams who demonstrate mindfulness in evaluating material sustainability or energy efficiency are more likely to encourage employees to propose alternative green solutions, even if these suggestions run counter to traditional practices. Empirical research further suggested that leader mindfulness reduces employees’ fear of criticism, thereby increasing their propensity to engage in green vocal behaviors. Therefore, we hypothesized the following:

H1: 

Mindfulness leadership positively influences green voice behavior.

Mindful leaders help build quality relationships between leaders and employees, which foster a culture of trust and cooperation to promote green knowledge-sharing behaviors. They emphasize open communication and active listening, enabling employees to share specialized environmental knowledge without hesitation. For example, in interdisciplinary engineering teams, intentional leaders facilitate the exchange of insights on renewable materials or low-carbon technologies, bridging the gap between different areas of expertise. This collaborative atmosphere not only enhances the team’s collective ability to innovate sustainably but also aligns with social cognitive theory, in which observational learning and shared goals drive knowledge diffusion. Boiral et al. (2015) suggested that conscious leaders’ emphasis on ethical transparency motivates employees to contribute tacit green knowledge, viewing such behavior as morally aligned with organizational values [61]. Therefore, we hypothesized the following:

H2: 

Mindfulness leadership positively influences green knowledge-sharing behavior.

Finally, past research has also confirmed that leader mindfulness positively influences organizational citizenship behavior, which is characterized by altruism [62]. Mindfulness leadership strengthens green helping behavior by fostering empathy and shared responsibility. Mindful leaders who demonstrate compassion and ethical consistency inspire employees to support colleagues in overcoming environmental challenges. For example, in construction projects, leaders who prioritize waste reduction through mindful planning encourage team members to collaboratively troubleshoot resource inefficiencies, reinforcing a collective commitment to sustainability [63]. Therefore, we hypothesized the following:

H3: 

Mindfulness leadership positively influences green helping behavior.

2.3. Mindfulness Leadership and Moral Identity

Moral identity refers to the extent to which moral traits (e.g., honesty, fairness) form a central component of an individual’s self-concept. From a social cognitive standpoint, it represents a stable and sophisticated cognitive framework comprising moral values, objectives, characteristics, and behavioral patterns [64]. It serves as a cognitive schema that actively filters and interprets morally relevant experiences and influences individuals’ perceptions and decisions [65]. Therefore, the “centrality” of moral identity determines its influence on behavior. Due to individual differences in cognitive frameworks, the salience of this trait in self-concept varies among individuals [64,66]. Furthermore, moral identity is not static but evolves through continuous social interaction and self-reflection. In engineering project design organizations, organizational factors (e.g., leadership) affect moral identity. For instance, mindfulness leadership can amplify designers’ prioritization of moral values, whereas toxic environments (e.g., limited time and resources) may suppress moral expression.

Mindfulness leadership is rooted in core values while openly questioning assumptions and embracing adaptive change. It advocates self-reflection and growth. Mindfulness leadership signals to employees that self-improvement is both attainable and expected. Mindful leaders foster moral identity by prioritizing moral awareness and transparent decisions, and thus offer employees clear moral guidance (e.g., making moral judgments). They also align values and actions by maintaining acute attention to internal principles and external environmental influences. Eisenbeiss and Van Knippenberg (2015) argued that mindful leaders bridge personal ethics and organizational sustainability goals, which encourages employees to adopt green values as intrinsic to their identity [67]. The previous studies confirmed that mindfulness practices can sharpen self-awareness and reduce cognitive dissonance between values and behaviors. Hence, mindfulness leadership acts as a promoter for moral growth, transforming abstract values into practical actions through self-reflection, moral modeling, and the alignment of both personal and organizational purpose. As a result, mindfulness leadership will strengthen moral identity by reinforcing moral alignment over time. Therefore, this study proposes the following hypothesis:

H4: 

Mindfulness leadership positively influences employees’ moral identity.

2.4. Moral Identity and Green Behaviors

Green behavior is fundamentally moral and is shaped by various individual moral traits, including moral character, moral reasoning, and moral commitment [65,68,69]. The validity of moral identity centrality under social cognitive theory in predicting moral behavior is further confirmed by considering the influence of situational factors on moral behavior [65]. When moral traits are core to one’s self-concept, individuals are more inclined to engage in moral actions to uphold moral values, as the identity becomes a readily accessible motivator [66]. Drawing from social cognitive theory, moral identity guides behavior through internalized moral values and self-regulatory mechanisms [18]. Blasi (1983) posited that individuals are primarily motivated to maintain internal self-coherence to avoid cognitive dissonance and feelings of guilt [70]. Specifically, when environmental values, such as nature conservation, are deeply ingrained in one’s self-concept, it fosters a profound sense of moral duty, prompting individuals to actively participate in environmentally friendly practices as a demonstration of responsible behavior.

Recent studies have shown that moral identity is significantly positively correlated with employees’ voice behavior [23,71,72]. Furthermore, individuals with identified moral beliefs are less influenced by external environmental pressures and are more likely to act according to their convictions. Therefore, engineering project designers with a strong moral identity actively participate in green design, expressing views and suggestions on environmentally friendly design even when others hold different opinions. Thus, this study hypothesized the following:

H5: 

Moral identity positively influences employee green voice behavior.

Engineering project designers are usually stuck in a moral dilemma, wondering whether to share knowledge [73]. To overcome this challenge, Wu (2021) [74] argued that ethical leaders can bolster employees’ moral identity through the transmission of ethical principles, thereby fostering a culture of knowledge sharing among subordinates. Consequently, within knowledge-intensive engineering project design organizations, designers who strongly identify with moral values are inclined to engage in proactive sharing of environmental expertise when confronted with moral dilemmas. Thus, this study hypothesized the following:

H6: 

Moral identity positively influences employee green knowledge-sharing behavior.

Previous studies have confirmed the effectiveness of moral identity in predicting prosocial behavior, including helping behavior [75,76]. Moral identity is related to broad moral concern and a sense of responsibility. Based on social cognitive theory, individuals with a high moral identity are more inclined to care about the well-being of others [69]. Therefore, they perceive helping others as meaningful and consistent with their true self, reflecting their values. Thus, this study hypothesized the following:

H7: 

Moral identity positively influences employee green helping behavior.

2.5. The Mediating Role of Moral Identity

As stated above, mindfulness leadership plays a crucial role in reinforcing the moral identity of project designers by exemplifying moral behavior. Drawing from social cognition theory, it is posited that individuals can develop self-awareness through observational learning [18]. Building on social cognitive theory, employees interpret cues from the organizational context to obtain a sense of themselves, which guides behavioral reactions in the workplace [77,78]. Mindfulness leadership effectively instills moral consciousness in their subordinates through three primary mechanisms: demonstrating moral behavior, fostering psychological safety, and aligning values, thereby nurturing their moral character. Kim and Choi (2021) demonstrated that employees can internalize environmental values before transforming leadership signals into actionable recommendations [79]. Furthermore, social cognitive theory underscores the significance of identity in shaping employee conduct [18]. It elucidates how preexisting internal cognitive frameworks and self-perceptions influence individual actions. According to this theory, individuals actively engage with external stimuli by processing and evaluating cues through cognitive processes, rather than being solely shaped by their surroundings, thereby impacting their behavior [80]. Similarly, Al-Ansi and Han (2019) found that employees who strongly identify with moral values perceive engagement in sustainable tasks as a moral duty rather than a mere compliance obligation [63]. Additionally, this theory states that individuals are broadly motivated and regulated in their behavior through ongoing self-influence [81]. Specifically, in the context of engineering project designers, a sense of fulfillment is derived from engaging in environmentally responsible practices to promote sustainability and advance organizational interests, thereby maintaining internal coherence. When designers deviate from their internal cognitive frameworks, they experience cognitive dissonance and guilt, prompting them to realign their actions with their deeply held values. Therefore, designers can assimilate green principles or norms through leader exemplification and then convert abstract values into goal-directed behaviors by moral identity. Thus, we hypothesized the following:

H8: 

Moral identity mediates the indirect effects of mindfulness leadership on (a) green voice behavior, (b) green knowledge-sharing behavior, and (c) green helping behavior.

• and Figure 1

3. Methodology

3.1. Sample and Procedures

This research obeyed the positivist paradigm of Grix (2018) and adopted a quantitative study to verify the hypothetical-deductive generalizations [82]. This study integrates the literature and theoretical research related to leader mindfulness, moral identity, green voice behavior, green knowledge-sharing behavior, and green helping behavior. It establishes a structural model that includes the interactions and relationships among the five variables. A survey questionnaire has been designed to test this theoretical model. By collecting quantitative data, we facilitate data analysis and processing, which helps us to conduct research and testing on predictive models, leading to more accurate results. The first part describes important demographic information about the respondents, and the second part includes measures of the independent variable (mindfulness leadership), three dependent variables (green voice behavior, green knowledge-sharing behavior and green helping behavior), and the mediating variable (moral identity). A 5-point Likert scale rated all items from “1 = strongly disagree to 5 = strongly agree”.

This study translated the questionnaires based on the back-translation procedures of Brislin (1990) [83]. Firstly, the items in the questionnaire were translated into Chinese, with the main focus on maintaining the simplicity, clarity and accuracy of the concepts. Secondly, two experienced engineering project designers were invited to review the translated questionnaire to identify and address any discrepancies arising from the translation. Thirdly, two academic professors were invited to translate the questionnaire back into English. Throughout this process, we consistently paid attention to the equivalence of concepts between the latest version and the original version to ensure the accuracy of the translation.

This survey collected questionnaires through the “www.sojump.com (accessed on 3 April 2025)” online survey questionnaire website from November 2024 to February 2025. Due to the nature of the target respondents, who are members of the engineering project design team, generalized probability sampling was insufficient in acquiring an adequate sample size. Therefore, to expand the sample size, the authors employed a snowball sampling method, in which the initial respondents recommended new participants or provided contact information for eligible new participants. According to Naderifar et al. (2017) [84], this method facilitates deeper data collection and research in this exploratory study, offering greater flexibility. While enhancing efficiency, it also allows for a broader scope, leading to more comprehensive data. However, the potential bias it introduces is a limitation that cannot be ignored. We have also actively taken corresponding measures to address the impact of analyzing this bias. After contacting these potential respondents and ensuring their willingness to participate in the survey, new sample data were obtained, and repeated referrals were made to new available participants. Ultimately, a total of 323 questionnaires were returned, with 267 valid responses used for statistical analysis, representing a valid response rate of 82.67%. The basic information of the respondents is exhibited in

Table 1. Demographics and profile of respondents (n = 267).

Variable	Category	Number	Percentage
Gender	Male	133	49.8%
	Female	134	50.2%
Age	Below 25	40	15.0%
	26–35	42	15.7%
	36–45	106	39.7%
	Above 45	79	29.6%
Education level	Below junior college	39	14.6%
	Undergraduate	43	16.1%
	Postgraduate	117	43.8%
	PhD	68	25.5%
Position	General employees	34	12.7%
	Line manager	70	26.3%
	Middle manager	101	37.8%
	Senior manager	62	23.2%
Work experience	0–5	30	11.2%
	6–10	67	25.1%
	11–15	111	41.6%
	>15	59	22.1%

.

3.2. Measurements

The assessment utilized a five-point Likert scale ranging from “strongly disagree = 1” to “strongly agree = 5” to gauge the variables, as detailed in

Table 2. Measurements and reliability.

Constructs and Items	Factor Loading	CR	Cronbach’s α	AVE
Mindfulness leadership		0.936	0.923	0.620
1. I have my supervisor’s full attention when I am speaking.	0.761
2. In conversations, my supervisor is impatient.	0.815
3. My supervisor is only half-listening when I am talking.	0.831
4. In conversations, my supervisor first listens to what I have to say, before forming his/her own opinion.	0.762
5. Before I have finished talking, my supervisor has already formed his/her own opinion.	0.792
6. My supervisor has a preconceived opinion about many topics and holds on to this opinion.	0.778
7. My supervisor stays calm even in tense situations.	0.768
8. My supervisor gets easily worked up.	0.810
9. When my supervisor does not like something, emotions can easily boil over.	0.764
Moral identity		0.943	0.935	0.562
1. It would make me feel good to be a person who has these characteristics.	0.735
2. Being someone who has these characteristics is an important part of who I am.	0.740
3. A big part of my emotional well-being is tied up in having these characteristics.	0.761
4. I would be ashamed to be a person who has these characteristics.	0.771
5. Having these characteristics is not really important to me.	0.766
6. Having these characteristics is an important part of my sense of self.	0.734
7. I strongly desire to have these characteristics.	0.763
8. I often buy products that communicate the fact that I have these characteristics.	0.758
9. I often wear clothes that identify me as having these characteristics.	0.741
10. The types of things I do in my spare time (e.g., hobbies) clearly identify me as having these characteristics.	0.686
11. The kinds of books and magazines that I read identify me as having these characteristics.	0.755
12. The fact that I have these characteristics is communicated to others by my membership in certain organizations.	0.792
13. I am actively involved in activities that communicate to others that I have these characteristics.	0.741
Green voice behavior		0.915	0.861	0.781
1. I make recommendations concerning environmental issues which affect my work.	0.886
2. I speak up and encourage others to get involved in issues that affect the environment.	0.873
3. I communicate my opinions about green work issues to others even my opinions are different and others at work disagree with me.	0.893
Green knowledge-sharing behavior		0.911	0.870	0.720
1. I share my environmental job-related experience with my co-workers.	0.869
2. I share my environmental expertise at the request of my co-workers.	0.822
3. I share my ideas about environmental issues with my co-workers.	0.851
4. I talk about my tips on environmental issues with my co-workers.	0.851
Green helping behavior		0.917	0.880	0.735
1. I am willing to help my co-workers to solve environmental-related issues.	0.874
2. I am willing to coordinate and communicate with my co-workers on environmental issues.	0.852
3. I am willing to cover environmental work-related assignments for co-workers when needed.	0.848
4. I am willing to assist new colleagues to adjust to the environmental work-related issues.	0.856

.

Mindfulness leadership was measured using 15 items from Schuh et al. (2019) [49]. The value of Cronbach’s alpha was 0.923. This issue involves an exploration of a leader’s emotions and habits, for instance, ‘My supervisor has a preconceived opinion about many topics and holds on to this opinion’.

Moral identity was measured by Zhang et al. (2022) [19], consisting of 12 factors. The internal consistency alpha was 0.935. Self-awareness is related to this issue, such as ’The fact that I have these characteristics is communicated to others by my membership in certain organizations.’

Green voice behavior was measured using 3 items adapted from Van Dyne and LePine (1998) [85]. The Cronbach’s reliability coefficient was 0.861. It includes one’s initiatives for the environment, such as ‘I speak up and encourage others to get involved in issues that affect the environment’.

Green knowledge-sharing behavior was measured using a 4-item scale developed by Lin (2007) [86]. The alpha coefficient was 0.870. This includes a tendency towards sharing, such as ‘I share my environmental job-related experience with my co-workers’.

Green helping behavior was measured by a 4-item scale from Farh et al. (1997) [87]. The Cronbach’s alpha reliability was 0.880. It shows the willingness to help, for example, ‘I am willing to coordinate and communicate with my co-workers on environmental issues’.

4. Results

4.1. Measurement Model

The reliability and validity of the measurement model were assessed through indicator reliability, construct reliability, convergent validity, and discriminant validity [88].

The factor loadings indicate the strength of the relationship between the original variables and common factors. Therefore, indicator reliability was tested by factor loadings, with larger absolute values meaning greater importance. Table 2 shows that almost all factor loadings are greater than 0.7 [88], indicating that the indicator reliability is acceptable. Internal construct reliability was evaluated by composite reliability (CR) and Cronbach’s alpha. Composite reliability (CR) with values above 0.7 indicates strong consistency, and Cronbach’s alpha with values above 0.7 indicates strong correlations between items and higher reliability. As shown in Table 2, Cronbach’s alpha coefficients (0.861–0.935) are all greater than 0.8, and the CR values (0.911–0.943) are all greater than 0.9 [89], demonstrating excellent internal consistency.

Regarding the convergent validity of the survey instrument, the average variance extraction (AVE) test was adopted. Average variance extracted (AVE) values between 0.5 and 0.7 suggest a good explanation of observed variable variance by latent variables. All the values of AVE in Table 2 (0.562–0.781) exceed the recommended value of 0.5 [89], which proves that the convergent validity of all the measurement constructs is satisfactory. Furthermore, to ensure the independence of indicators within different structures, the heterotrait–monotrait (HTMT) ratio was used to test discriminant validity.

Table 3. Discriminant validity HTMT ratio criterion.

	MI	ML	GVB	GKSB	GHB
MI
ML	0.388
GVB	0.519	0.494
GKSB	0.550	0.473	0.561
GHB	0.647	0.575	0.622	0.734

MI = moral identity, ML = mindfulness leadership, GVB = green voice behavior, GKSB = green knowledge-sharing behavior, GHB = green helping behavior.

indicates that all HTMT were less than 0.85 [90], demonstrating that the discriminant validity is acceptable.

4.2. Common Method Bias

Quantitative data were collected through self-reported questionnaires from a single source, potentially leading to common method variance. To address this issue, we allocate inquiries concerning independent and dependent variables across the sections of the survey to prevent logical or temporal sequencing. Furthermore, we continuously enhance the formulation of questions to guarantee clarity and precision. To further minimize bias and promote attentive reading, we incorporate reverse-scored items. Accordingly, Harman’s one-way test was employed to evaluate the constraints of statistical approaches [91]. Results indicate that the initial factor contributed 37.661% to the total variance, falling below 50% [92]. Hence, this research is not significantly affected by common method variance.

4.3. Structural Model

The study developed a structural model to confirm hypotheses concerning mindfulness leadership, moral identity, green voice behavior, green knowledge-sharing behavior, and green helping behavior within engineering project designer teams. The data were analyzed using structural equation modeling, yielding satisfactory outcomes for standardized path coefficients and model validity. In Figure 2, the coefficients of determination R² of all endogenous constructs are 0.131, 0.309, 0.319, and 0.453, indicating a good model explanatory power [93]. Considering the predictive correlation of the structural model, this study uses the cross-validated redundancy index (Q²) for testing. All endogenous constructs demonstrated Q² values (0.074–0.328) above 0 [89] (Figure 2), indicating a satisfactory predictive correlation within the model.

Figure 2 shows the results of the data analysis, indicating that mindfulness leadership has a positive effect on green voice behavior (β = 0.313, t = 5.776, p < 0.001), green knowledge-sharing behavior (β = 0.281, t = 4.998, p < 0.001), and green helping behavior (β = 0.353, t = 7.217, p < 0.001). The analysis provides evidence for H1, H2, and H3. In addition, the results support H4, demonstrating that mindfulness leadership has a positive impact on moral identity (β = 0.366, t = 7.482, p < 0.001). At the same time, moral identity is proven to have a significant positive impact on green voice behavior (β = 0.359, t = 7.138, p < 0.001), green knowledge-sharing behavior (β = 0.403, t = 7.789, p < 0.001), and green helping behavior (β = 0.461, t = 9.837, p < 0.001). H5, H6, and H7 are strongly supported. Finally, a 95% confidence interval was used to test the mediating effect of moral identity. The results show that moral identity has a significant positive mediating effect between leader mindfulness and green voice behavior (β = 0.131, t = 5.165, p < 0.001), leader mindfulness and green knowledge-sharing behavior (β = 0.147, t = 5.836, p < 0.001), as well as leader mindfulness and green helping behavior (β = 0.169, t = 6.716, p < 0.001). Therefore, H8a, H8b, and H8c are supported.

5. Discussions and Implications

The inherent tension between profit maximization imperatives and ecological preservation mandates constitutes a fundamental dilemma for engineering project designers. Within this context, designers’ decisions in operationalizing green principles into design outcomes directly impact the project-level environmental performance [4,6]. Consequently, this situation underscores the urgent need for leadership intervention to effectively guide design organizations in balancing project requirements while proactively embracing environmental responsibility. While extant research has established leaders as a catalyst for individual pro-environmental behavior [14]. Nevertheless, green practices in knowledge-intensive engineering project design organizations are inherently collaborative, relying on interdisciplinary collaboration [94]. Grounded in social cognitive theory, this investigation addresses a critical knowledge gap by examining how mindfulness leadership stimulates green behaviors within designer collaborations, with moral identity serving as a mediating mechanism. The green behaviors include green voice behavior, green knowledge-sharing behavior and green helping behavior. Thereby, it enhances our understanding of the mechanisms driving green behaviors in a project organization’s context. Through an empirical study, this study explores the complex process by which mindfulness leadership influences these green behaviors. Moral identity is an important psychological factor influencing designers’ green behaviors and mediates the effect of mindfulness leadership on these green behaviors.

5.1. Major Findings and Theoretical Implications

Firstly, the validation of H1–H3 elucidates that mindfulness leadership significantly promotes engineering project designers’ green behaviors, especially green voice behavior, green knowledge-sharing behavior, and green helping behavior. Prior research has established a positive association between mindfulness and sustainable behavior [95,96,97]. Extension to the organizational field, mindfulness leadership exhibits higher sensitivity towards environmental concerns and is more inclined to encourage eco-friendly initiatives in their decision-making processes. The finding of this study aligns with Yang et al. (2024), that demonstrated that mindfulness leadership enhances the environmental sensitivity of employees through mindfulness transmission, creating a trusting and inclusive organizational atmosphere for employees, directly stimulating their environmental awareness, thereby encouraging their proactive responses to environmental uncertainties and environmentally friendly practices [14]. Our research indicates that mindfulness leadership characterized by environmental insight and present-moment focus supports environmentally friendly designing solutions that embody ecological concepts and foster a commitment to environmental friendliness. Such leaders help project designers clarify their environmental sustainability goals, inspire sustainable design principles, challenge the status quo, and reduce the overemphasis on economic benefits. In addition, unlike prior research that concentrated on stable environments, the dynamics and complexity of engineering projects (e.g., time pressures, resource constraints) necessitate leaders to possess adaptive cognitive abilities. Mindfulness leadership enables designers to maintain a dynamic balance between technical feasibility and environmental accountability by emphasizing present-moment attention and non-evaluative awareness.

Arendt et al. (2019) have indicated that mindfulness leadership significantly influences leader–follower communication by enabling leaders to attentively listen to and nonjudgmentally consider employees’ ideas for integration into their decision-making processes [60]. Our study aligns with these findings and extends them by illustrating that the friendly communication atmosphere fostered by mindfulness leadership can empower employees to voice their perspectives and recommendations on environmental concerns. According to Ni et al. (2023) [62], mindfulness leadership is associated with increased interpersonal organizational citizenship behavior among team members. Mindful leaders cultivate empathetic concern and encourage members to understand others’ feelings and needs. Our study further demonstrates that mindfulness leadership alleviates employee stress and negative emotions by keenly perceiving employee needs and providing emotional and cognitive support, thereby fostering an atmosphere of trust, inclusiveness, and friendly collaboration. This atmosphere reduces the psychological insecurity of engineering project designers, making them perceive support and inclusion, thereby promoting interdisciplinary collaboration among designers in enhancing solutions for environmental challenges. Furthermore, organizational culture plays a key role in amplifying the effects of mindful leadership. In organizations with strong environmental values and collaborative norms, the alignment between leaders’ mindfulness practices and employees’ green behaviors may be enhanced.

Secondly, the support for H4 indicates that mindfulness leadership, a positive leadership style, effectively strengthens designers’ moral identity. This finding aligns with Allen and Fry (2023) [98], which showed that leaders drive followers’ moral development through role modeling. Notably, mindfulness has been found to have a significant positive correlation with moral decision making [48]. From a social cognitive perspective, mindfulness leadership showcases environmentally conscious decision making through transparent discussions on moral dilemmas concerning environmental matters, thereby embodying its environmental values and enabling employees to integrate this ethos into their self-identity. This not only encourages moral decision making but also fosters employees’ responsibility for the outcomes of their actions, both professionally and socially. Furthermore, Stets and Carter (2012) [66] considered that organizational factors can activate individual moral identity, thereby increasing the salience of environmental values in their working self-concept. Expanding on the research of Stets and Carter (2012), this study argues that mindfulness leadership constructs an organizational factor conducive to moral reflection through non-judgmental communication [66]. This approach encourages designers to consider the environmental impact of their engineering solutions, thus activating moral cognitive frameworks and enhancing the centrality of their moral identity. Ultimately, designers are more likely to view their work through the lens of environmental sustainability and moral responsibility.

Thirdly, our findings (H5–H7) confirm that moral identity serves as a crucial psychological mechanism influencing the green behaviors of engineering project designers. Specifically, designers with strong moral identities tend to internalize environmental norms and actively engage in sustainable practices throughout the design process. They view minimizing the environmental impact of project implementation as a personal responsibility and experience guilt over any environmental harm resulting from their design choices. Consequently, these designers prioritize green principles, such as selecting eco-friendly materials and construction techniques. Moreover, the inherently altruistic nature of moral identity drives designers to reduce self-serving tendencies and focus on the well-being of others, thereby fostering harmonious communication and effective collaboration, such as sharing and helping. Our results align with Abbas and Bashir’s (2020) [99], who suggested that moral identity enhances employees’ awareness of environmental consequences and their responsibilities, leading to a sense of obligation to engage in behaviors benefiting both others and the environment.

According to social cognitive theory, moral identity is an internal self-regulation driven by the principle of coherence [64]. Individuals with a strong moral identity tend to align their behavior with their internalized moral principles, resulting in a deeper commitment to sustainability, as their self-awareness draws boundaries for behavior [100]. In this case, designers are not merely reacting to external pressures, but are also driven by an intrinsic motivation to minimize harm to the environment during the design process. Therefore, this study emphasizes that when examining the green practices of engineering project designers, the psychological mechanisms from a moral perspective should also be considered, which is confirmed by H5–H7. This study emphasizes the importance of considering psychological mechanisms from a moral perspective when examining the green practices of engineering project designers, a notion further supported by H5–H7.

Finally, this study unveils the underlying mechanism by which mindfulness leadership influences engineering project designers’ green behaviors from a moral perspective. The findings of H8 support the mediating role of moral identity between mindfulness leadership and green behavior. Previous research has primarily focused on the impact of mindful leaders’ beliefs on task performance in organizational settings [44,49,52,101,102]. These studies have highlighted the promotion of high-quality superior–subordinate relationships, interpersonal justice, improved communication quality, and enhanced employee psychological satisfaction. However, positive work outcomes, specifically moral behaviors, are usually overlooked. In engineering project design organizations, designers’ design decisions often involve trade-offs between economic and environmental considerations, essentially constituting moral decisions. This study demonstrates that mindfulness leadership promotes green practices by shaping the moral identity of subordinates. Specifically, as engineering project designers perceive greater mindfulness leadership, they become more attuned to the moral cues demonstrated by leaders, leading to an enhanced self-concept, heightened moral identity, and consequently, improved green practices in the design process. In addition, mindfulness leadership creates a sustainable and supportive atmosphere that enhances designers’ job satisfaction, fosters their sense of moral responsibility, and promotes their environmental practices in the engineering design process. From the perspective of social cognitive theory, this study validates the mediating role of moral identity between mindfulness leadership and employees’ green practices. These findings address a significant research gap by examining how mindfulness leadership affects green behaviors in engineering project design organizations.

5.2. Practical Implications

This study concentrates on the pivotal role of mindfulness leadership in shaping the moral identity of engineering project designers and its subsequent impact on their green behaviors: green voice behavior, green knowledge-sharing behavior and green helping behavior. The findings provide some implications for practice.

Mindfulness leadership has received significant attention in recent years, substantially enhances employees’ green behaviors in engineering project design organizations. Consequently, engineering project design organizations are encouraged to cultivate mindfulness through the strategic selection of capable organizational managers and the implementation of systematic organizational measures. According to Johnson et al. (2020) and van Dongen et al. (2016), it is crucial for engineering enterprises that the impact of mindfulness initiatives may not be immediate, necessitating engineering companies to weigh the initial investment against potential long-term advantages [103]. For instance, introducing mindfulness training programs, such as brief 10 min meditations or breathing exercises following daily meetings, can help managers develop non-judgmental awareness of present experiences. Additionally, managers should continually employ mindful practices to motivate designers’ green behaviors. Firstly, they can establish a supportive culture in daily management processes by encouraging open communication and feedback. However, this will inevitably reduce the decision-making efficiency of the project, especially in projects with tight deadlines. Therefore, leaders need to set fixed feedback times to balance openness and decision-making efficiency. In addition, the organization fosters a culture that prioritizes sustainability by establishing transparent and achievable environmental goals, recognizing employees’ green contributions, and integrating ecological values into daily operations. This approach empowers designers to express their views and suggestions on environmental issues during design discussions, even if these suggestions are not immediately accepted. Secondly, leaders actively impart their knowledge and experience in solving environmental problems during the design process. They can utilize open-source platforms, interdisciplinary collaboration tools, or develop proprietary knowledge repositories to centralize environmental protection cases, thereby fostering enhanced knowledge dissemination in green design. Finally, leaders can create collaborative groups for green design tasks. By promoting environmental support among designers through mindfulness and empathy, leaders can facilitate collaborative problem solving in green design issues. Additionally, mindful practices are realized by setting specific sustainability key performance indicators (e.g., clear waste reduction targets) to ensure the feasibility and effectiveness of interventions.

Our findings underscore the crucial role of moral identity as a proactive psychological motivator in motivating designers’ green behaviors. In light of this, engineering project design organizations should implement a series of targeted measures to enhance the moral identity of designers. Firstly, engineering project design organizations can incorporate green design concepts and moral values as key evaluation criteria in their recruitment and promotion processes. This approach ensures that designers with a strong moral orientation and commitment to sustainability are given priority in hiring and career advancement. Secondly, managers can cultivate a moral climate focused on ecological protection. In this climate, designers could align their personal ethics with an organization’s sustainable development goals. Engineering project design organizations should reward designers who exemplify green principles in their designs and demonstrate green behaviors, such as proposing environmentally friendly designs, sharing knowledge of sustainable design practices, or assisting colleagues in addressing environmental challenges. By fostering an environment that values and rewards moral behavior and sustainable practices, organizations can nurture the moral values of their designers. This, in turn, encourages designers to integrate environmentally friendly principles into their self-concept, creating a workforce that is intrinsically motivated to pursue green design solutions.

5.3. Limitations and Future Directions

Despite the contributions to theory and practice, this study has certain limitations. First, the primary source of samples was confined to engineering project design organizations. This industry-specific focus may restrict the generalizability of our findings to other sectors. Thus, future research can evaluate our findings in other sectors. Second, data collection relied predominantly on self-report questionnaires at the same time. This approach may introduce common method bias. This study employed procedural remedies and statistical remedies to reduce common method bias. Although the results show that common method bias was not serious, longitudinal research is encouraged to mitigate it directly in the future.

Some unanswered questions need further exploration. Although the mediating role of moral identity was validated, other potential psychological mechanisms were not examined. Hence, future studies could consider other psychological mechanisms (e.g., psychological empowerment, psychological resilience) in the relationship between mindfulness leadership and designers’ green behaviors, as well as further exploring the moderating effects of contextual factors (such as organizational support, organizational green policies, and external regulatory pressure) to refine the theoretical model and define boundary conditions.