The E ﬀ ect of Corporate Social Responsibility on Employees’ Organizational Citizenship Behavior: A Moderated Mediation Model of Grit and Meaning Orientation

: Even though research on the micro-e ﬀ ects of corporate social responsibility (CSR) has been growing, our understanding of the psychological mechanisms through which perceived CSR a ﬀ ects employees’ organizational citizenship behavior (OCB) remains insu ﬃ cient. Based on social identity theory and the concept of whole self, this study examines the mediating role of meaning orientation as a psychological mechanism and tests the moderating role of grit, using survey data collected from 361 South Korean workers. Our results show that the positive association between perceived CSR and OCB is mediated by meaning orientation. In addition, grit strengthens the perceived CSR-meaning orientation relationship, which in turn boosts employees’ OCB. This study contributes to the literature by revealing a psychological mechanism and how it is moderated by individual traits, which are crucial in predicting CSR’s micro-e ﬀ ects. We discuss how our results can be practically applied by organizations as part of sustainable human resource management.


Introduction
In recent years, corporate social responsibility (CSR) has attracted the attention of both business and academia. Over 90% of global companies have implemented CSR [1], and nearly half of all CSR-related studies have been published in recent decades [2]. CSR has been recognized as an especially important issue in corporate sustainable management [3]. Empirical research has shown that CSR has positive impacts on macro-level and micro-level outcomes simultaneously, enabling businesses to engage in sustainable management. At the macro-level, studies show that CSR positively influences financial performance and marketing [2,4,5]. At the micro-level, empirical research has shown that CSR positively affects job satisfaction [6], organizational identification [7], organizational citizenship behavior (OCB) [8], and work engagement [9].
While CSR is a key factor in the sustainable management of an organization, organizational citizenship behavior (OCB) is an important factor at the individual level. To survive and grow in an excessively competitive environment, companies require individuals to be willing to perform more functions than those specified in their job descriptions, as well as to be actively dedicated to their organizations [10]. In addition, instead of top-down approaches by leaders, voluntary actions by employees are required for an organization's culture to naturally internalize the strategy of sustainable management. In this regard, OCB, or extra-role activities performed by individuals within within an organization, has long been advocated, especially in the field of organizational psychology and management [11][12][13].
Several attempts have been made to explore the relationship between CSR and OCB empirically. Research has consistently shown that an organization's CSR plays a significant role in promoting employees' OCB [14][15][16][17]. However, how and why CSR positively affects OCB has not yet been investigated. In this study, we use social identity theory (SIT) [18] and the concept of whole self [19,20] as the theoretical framework to account for the relationship between CSR and OCB. Based on the two theories, we expect that when employees perceive that their organization is committed to CSR, it provides them a safe environment in which to pursue meaning in their work and boosts their OCB. Thus, in this research, we aim to investigate the impact of perceived CSR on OCB, while examining employees' meaning orientation as a mediator, which can explain the positive relationship between perceived CSR and OCB.
The extent to which CSR's positive effect on OCB manifests can vary according to individual characteristics. In this study, we investigate grit, the passion and perseverance for a long-term goal [21], which can play a role as a potential moderator. Empirical studies have shown that those with high levels of grit tend to pursue other-oriented and meaning-oriented lives [22][23][24]. We present a moderated mediation model in Figure 1; in this model, we hypothesize that employees with high levels of grit are more likely to pursue meaningfulness at work in response to their CSR perceptions. We investigated our hypotheses based on moderated mediation model ( Figure 1). By examining the underlying psychological mechanism and the moderating role of individual traits, we expect this study to expand the literature by showing why and for whom perceived CSR promotes OCB.
This research paper proceeds as follows. Following the introduction, it discusses the theoretical backgrounds and proposes the hypotheses. Then, the materials and methods and the results are presented, followed by the discussion and conclusion.

Perceived CSR and OCB
CSR refers to an organization's behavior that goes beyond mere profits to support society's ethical, resource, social, and environmental goals [25,26]. For a long time, CSR research was mainly conducted in the fields of public relations and business administration from a macro perspective, focusing on financial performance and marketing effects [2,4,5]. However, a macro perspective of CSR, which neglects importance of a micro understanding of CSR renders it difficult to identify the true effects of CSR [6]. Glavas and Kelly [6] argue that collaboration between business administrators and psychologists is crucial in order to research CSR from a micro perspective.
Scholars in organizational psychology and management have responded to this call and are focusing more attention on the impact of CSR on individual behavior and attitudes [6,27,28]. CSR has been found to have a consistently positive effect on employees' attitudes and behaviors. For instance, This research paper proceeds as follows. Following the introduction, it discusses the theoretical backgrounds and proposes the hypotheses. Then, the materials and methods and the results are presented, followed by the discussion and conclusion.

Perceived CSR and OCB
CSR refers to an organization's behavior that goes beyond mere profits to support society's ethical, resource, social, and environmental goals [25,26]. For a long time, CSR research was mainly conducted in the fields of public relations and business administration from a macro perspective, focusing on financial performance and marketing effects [2,4,5]. However, a macro perspective of CSR, which neglects importance of a micro understanding of CSR renders it difficult to identify the true effects of CSR [6]. Glavas and Kelly [6] argue that collaboration between business administrators and psychologists is crucial in order to research CSR from a micro perspective. Scholars in organizational psychology and management have responded to this call and are focusing more attention on the impact of CSR on individual behavior and attitudes [6,27,28]. CSR has been found to have a consistently positive effect on employees' attitudes and behaviors. For instance, CSR is strongly related to job satisfaction [6], organizational identification [7], work engagement [9], and OCB [8,17,29].
In this study, we investigate the effects of perceived CSR on OCB. In a competitive economy, employees' extra-role behavior and helping behavior is essential for companies to survive [10]. Specifically, Chowdhury [30] shows that OCB plays a significant role in a corporation's sustainability performance. The importance of OCB has long been recognized, especially in the field of organizational psychology and management [11][12][13]. However, the characteristics of OCB are not limited to helping behaviors. Meta-analysis [31] shows that individuals who are more engaged in OCB demonstrate better performance. Grant [32] characterizes successful people in their career field as "givers"; these are individuals who are not obsessed with the principle of short-term reciprocity, who give to others, and who work for the overall benefit of an organization instead of themselves. Thus, OCB has been drawing great attention not only from academia but also from the general public as a hallmark of a life of giving.
As greater attention has been given to OCB, scholars have been struggling to understand what drives employees' OCB. The antecedents of OCB have been studied from several aspects. At the individual level, positive affect [33], intrinsic motivation [34], and grit [35,36] are predictors of employees' OCB. At the organizational level, organizational support, organizational justice [37], and CSR [29,38] are predictors of OCB.
Among the various studies of OCB, some attempts have been made to examine a causal relationship between perceived CSR and OCB. Oo and colleagues [17] apply SIT, claiming that employees tend to feel a sense of pride when they perceive their companies actively implementing CSR activities, because the organizations can be seen as more responsible and prestigious by outsiders. An increased sense of pride fosters an individual's commitment [39], job satisfaction [40], creativity, and even OCB [17]. Alternatively, the social exchange theory presented by Blau [41] can be used to explain the relationship between perceived CSR and OCB. Farid and colleagues [42] claim that when employees perceive the organization as fair, they tend to show more cooperative behavior in return as part of a reciprocal relationship. Lastly, the concept of whole self [19,20] can be an alternative explanation based on the innate human desire to develop a sense of purpose and meaning at work. As employees are challenged in finding purpose and meaning at their workplaces, working in organizations with active CSR can be seen as fulfilling their basic need for meaning by allowing them to contribute to a great purpose [43]. In this regard, Raub and Blunschi [44] suggest that when employees are aware of their companies' CSR, they tend to exhibit high levels of helping and voice behavior and job satisfaction, because the CSR activities give their tasks more significance. Taken together, we hypothesize that employees' perceived CSR will foster their OCB. Hypothesis 1. Employees' perceived CSR will be positively related to their OCB.

Meaning Orientation as a Mediator
Humans have a need for meaning in their lives at a basic level. Frankl [45] famously showed how people do not give up seeking purpose and meaning in life even in desperate situations such as World War II. Similarly, Seligman [46] introduces the concept of meaning orientation as one of three orientations for happiness (i.e., pleasure, meaning, and engagement). He argues that the pursuit of meaning is a basic need, which is required to secure happiness. The conceptual source for meaning orientation is Aristotle's idea of eudaimonic happiness, which considers true happiness to be developing and using one's skills and talents for the greater good [47]. Seligman [46] further develops Aristotle's philosophical perspective on happiness by asserting that individuals discover the meaning of life in the process of developing their talents and working for the well-being of others in society, Sustainability 2020, 12, 5411 4 of 14 which leads to a better life. Empirical research on meaning orientation has consistently shown that pursuing meaning is closely related to psychological well-being [47,48].
Previous research has shown that employees' perceived CSR can foster their experiences of meaningfulness at work [44,49]. In this study we use the concept of whole self [19,20] and SIT [18] as the theoretical framework to link CSR and OCB. The two theories are interchangeable, as both assume that individuals tend to derive a sense of self from the organization's identity. According to the perspective of whole self [19,20], humans have an innate desire to have a sense of purpose and meaning and to contribute to society. However, few workers are allowed sufficient opportunities to find purpose in their work. In this regard, the organization's positive identity created by CSR can be an adequate alternative avenue for workers to contribute to a greater purpose [43], which in turn fosters positive work outcomes. Even though the job itself may not be directly related to helping others, working at an organization with CSR enables them to find purpose and meaning in their work by letting them feel connected to a larger purpose. In addition, SIT suggests that individuals tend to feel an increased sense of self-esteem and pride when they belong to organizations with strong reputations among outsiders [50,51]. Increased self-esteem and pride can increase the meaningfulness of work [52], which in turn leads to positive behaviors at work. Taken together, we posit that CSR affects individuals' orientation to meaning at work, which in turn increases their helping and extra-role behaviors.

Hypothesis 2.
Meaning orientation will mediate the relationship between perceived CSR and OCB.

Grit as a Moderator
The extent to which CSR's positive effect on OCB manifests can vary according to individual characteristics. For example, Gully et al. [53] show that the positive impact of CSR can vary depending on individuals' attitudes or traits. Specifically, previous research has shown that those who were more engaged in other-oriented values were more attracted to organizations with CSR [52,53]. In this study, we investigate how the individual-level variable grit, the passion and perseverance for a long-term goal [21], can play a role as a potential moderator.
Grit is a well-known non-cognitive factor that predicts career success [21]. Grit has been found to predict achievements better than IQ and conscientiousness [21], which are well-known antecedents of achievements. Individuals with higher levels of grit in the workplace are expected to perform better and to remain in their field of work longer [21,[54][55][56]. However, gritty people are expected not only to perform their jobs faithfully but also to exhibit positive behaviors in the workplace. Duckworth [22] asserts that grit as an individual characteristic is highly related to other-oriented and socially motivated characteristics. That is, grit is not limited to individuals' career success or reputation, it extends to interest in others' well-being.
In Grit, Duckworth [22] argues that the ultimate goals of gritty people include living prosocial, other-oriented, and meaningful lives. Because their goals are long-term, gritty people need constant motivation not to give up in the middle of the process. How do other-oriented goals motivate people with grit? Linking long-term goals with other-oriented and meaningful life can offer the constant source of motivation for gritty people. Construal level theory (CLT) [57], which considers events according to the psychological distance people experience personally, can support this notion. In this theory, psychologically far events are construed at a high level, while psychologically near events are construed at a lower level. People with high-level construal are more likely to think in abstract and in big-picture terms and exhibit a high level of self-control over momentary impulses compared to those with low-level construal [58]. Oh, Lee, and Sohn [59] show that gritty people are likely to perceive their goals as psychologically distant, which implies that they tend to construe the situation at a high level. Furthermore, CLT also suggests that purpose, which is a broad, abstract, and long-term concept, is highly related to high-level construal. Therefore, it is plausible that when gritty people pursue their goals, perceiving their goals as long-term and linking their long-term goals with other-oriented and purposeful life allow them to construe at a high level, and thus they can overcome short-term temptation and finally achieve their goals.
Researchers have shown empirically that grit is positively related to other-oriented life [24]. Other studies find that grit is highly related to prosocial behavior [23]. Regardless of the type of motivation (i.e., intrinsic motivation or prosocial motivation) an individual already possesses, grit is positively associated with prosocial behavior, which implies that gritty people seek not only career success but also purposeful and meaningful lives in which they act on behalf of others. In this regard, we expect that grit is an individual difference that moderates the relationship between perceived CSR and meaning orientation. Therefore, we hypothesize that grit will moderate the relationship between CSR and meaning orientation. Hypothesis 3. Grit moderates the relationship between perceived CSR and meaning orientation; the positive relationship between perceived CSR and meaning orientation will become stronger for employees who have higher levels of grit.

Participants
This study was approved by the university's Institutional Review Board. Korean workers over 20 years of age were randomly recruited by a data-collection company and completed a 15-min online survey, after which they received a monetary reward from the data-collection company. A total of 361 participants were recruited from many different organizations; the average age was 28.74 years (SD = 13.61), and 164 (45.4%) of the respondents were men. The participants' job ranks were employee (37.4%), assistant manager (20.5%), manager (17.7%), deputy general manager (8.6%), and general manager (12.7%). The participants worked for organizations of the following sizes: fewer than 10 workers (21.3%), 10-30 workers (18.3%), 30-100 workers (25.8%), 100-300 workers (16.6%), and more than 300 workers (18%).

Perceived Corporate Social Responsibility
To measure the extent to which participants perceive CSR, we used the CSR scale [60]. Of the scale's 17 items, nine items that assess CSR with regard to employees (CSR-E) and to social and nonsocial stakeholders (CSR-S) were used. The validity of these items has been established by previous studies [61]. Four items assess CSR-E (e.g., "Our company provides a wide range of indirect benefits to improve the quality of employees' lives") and five items assess CSR-S (e.g., "Our company targets sustainable growth which considers future generations"); each of the items was ranked on a five-point scale (1 = not like me at all, 5 = very much like me). The internal reliability of the scale, Cronbach's α was 0.92.

Organizational citizenship behavior
The OCB scale [33] consists of 16 items with a five-point scale (1 = not like me at all, 5 = very much like me) and was used to measure the extent to which participants exhibit OCB. The OCB scale is comprised of two sub scales: OCB to individual (OCB-I) and OCB to organization (OCB-O). Among 16 total items, 8 items assess OCB-I, which is related to behaviors that assist specific individuals (e.g., helping others who have been absent), and 8 items assess OCB-O, which is related to behaviors that assist the organization in general (e.g., making suggestions to improve the department). The internal reliability of this scale, Cronbach's α was 0.90.

Meaning Orientation
The Orientations to Happiness Scale [47] was used to measure the extent to which participants are motivated to pursue meaning. The original scale consists of three subscales (pleasure, meaning, and engagement). Pleasure orientation subscale assesses the extent to which participants are motivated to pursue pleasure, while engagement orientation and meaning orientation subscale measures participants' motivation to pursue engagement and meaning, respectively. In this study, only meaning orientation subscales, comprised of items assessing meaning orientation (e.g., "In choosing what to do, I always take into account whether it will benefit other people"), were used with a five-point scale (1 = not like me at all, 5 = very much like me). The internal reliability, Cronbach's α was 0.85.

Grit
The original grit scale (Grit-O) [55] consists of 12 items with a five-point scale (1 = not like me at all, 5 = very much like me) and was used to assess participants' grit-passion and perseverance for a long-term goal. Grit-O is comprised of two sub scales: perseverance and consistency of interest. Six items assess perseverance for a long-term goal (e.g., "I finish whatever I begin"), and six items assess the consistency of interest in a long-term goal (e.g., "I often set a goal but later choose to pursue a different one"). The internal reliability, Cronbach's α was 0.76.

Control Variables
As control variables, we included organization size and demographic variables, such as gender, age, tenure, and job ranking.

Analysis
Our moderated mediation model was analyzed according to the causal steps proposed in previous studies [62,63]. Unlike structural equation model analysis, which uses a confirmatory method based on having sufficient previous studies, we chose an exploratory method suited to analyzing a newly proposed relationship [64]. In this exploratory approach, we tested the statistical significance of the following relationships: the effect of CSR on OCB (Hypothesis 1), the mediating role of meaning orientation (Hypothesis 2), and the moderating effect of grit on the relationship between perceived CSR and meaning orientation (Hypothesis 3).
We conducted a preliminary analysis before proceeding with our moderated mediation model analysis. We found no univariate or multivariate outliers [65], no violations of the basic assumptions of linearity, and no multicollinearity. Following conventional guidelines [66], we investigated the kurtosis and skewness of all of our variables. The values for all of our variables were normally distributed and satisfied their cutoffs (skewness values > |3|, and kurtosis values > |1|).
Next, we conducted confirmatory factor analysis (CFA) using Mplus 6.0 to test the construct validity of our research model. To verify the moderated mediation model, we used the SPSS 25.0 and PROCESS macro [67]. First, we used regression analysis to verify the relationship between CSR and OCB (Hypothesis 1). Next, PROCESS model 4 was used to analyze the mediating effect of meaning orientation (Hypothesis 2). Lastly, PROCESS model 7 was used to examine the whole moderated mediation model (Hypothesis 3). Additionally, we used bootstrapping methodology to analyze the significance of the indirect effects [68,69]. We present unstandardized regression coefficients (b) in our results following the recommendation of Hayes [67].

Confirmatory Factor Analysis
First, we conducted confirmatory factor analysis (CFA) using Mplus 6.0 to assess the validity of our study variables. The CFA results are shown in Table 1. Overall, our research model (the five-factor measurement model) shows acceptable fit (CFI = 0.93, TLI = 0.90, SRMR = 0.048, RMSEA = 0.08) compared to other alternative models. The results indicate the discriminant validity of our research measurements and the low probability of common method bias.  Table 2 presents descriptive statistics for study variables (mean, standard deviations, and correlation coefficients). Most of our study variables are positively associated with each other, with the exception of CSR and grit.

Moderated Mediation Model
We conducted multiple linear regression to test Hypothesis 1, which suggested a positive association between perceived CSR and OCB. We entered control variables (gender, age, tenure, job rank, organization size) in the first block and CSR in the second block. The results presented in Table 3 show that perceived CSR is positively related to OCB (b = 0.36, p < 0.001), supporting Hypothesis 1.
To test Hypothesis 2, the mediating effect of meaning orientation, we utilized PROCESS macro [67], which was developed to test various mediation and moderation models. To test mediation effect of meaning orientation, model 4 (Process macro) and an additional 95% bias-corrected confidence interval with 5,000 bootstrapping method was utilized. The results in Table 3 indicate that meaning orientation mediates the positive relationship between perceived CSR and OCB (b = 0.14, BootSE = 0.03, Boot 95% CI = [0.09, 0.19]), supporting Hypothesis 2.
Lastly, we chose model 7 (PROCESS macro) to test the moderating effect of grit on the relationship between perceived CSR and meaning orientation, Hypothesis 3. Specifically, we hypothesized that the positive relationship between perceived CSR and meaning orientation would become stronger for employees who have a higher level of grit. The results show that the interaction term between perceived CSR and grit was statistically significant (b = 0.17, se = 0.05, p < 0.05; Table 3). Specifically, Sustainability 2020, 12, 5411 8 of 14 as the level of grit increases, the positive relationship between perceived CSR and meaning orientation becomes stronger (see Figure 2). In addition, the indirect effects of perceived CSR on OCB through meaning orientation vary according to the grit level. For high levels of grit (+1SD), the indirect effect was statistically significant (b = 0.17, BootSE = 0.03, 95% CI = [0.11, 0.23]). For low levels of grit (−1SD), the indirect effect was statistically significant but smaller (b = 0.10, BootSE = 0.03, 95% CI = [0.05, 0.16]). Figure 3 shows the indirect effects of CSR on OCB through meaning orientation across a range of values of grit. These results support Hypothesis 3.  Figure 3 shows the indirect effects of CSR on OCB through meaning orientation across a range of values of grit. These results support Hypothesis 3. Note: CSR = corporate social responsibility; *** p < 0.001, ** p < 0.01, * p < 0.05.

Theoretical and Practical Implications
This study contributes to the literature by testing a moderated mediation model of the effect of CSR on employees' OCB. We explored how the positive effect of employee's perceived CSR on OCB was mediated by meaning orientation. We also found that this indirect effect was moderated by individuals' grit levels. To be specific, when gritty people perceived their companies' CSR, they were more likely to pursue meaning, which in turn led them to engage in more OCB.
Our study makes valuable contribution by expanding our understanding about the benefits of CSR for employees. While prior studies on CSR have mostly focused on its macro effects (e.g., financial performance) [2,4,5], our research focused on its micro-effects on employees' attitudes and behaviors. We found that organizations' active engagement in CSR can spur employees to pursue deep meaning in their work and to perform more helping and extra-role behavior. Compared to topdown approaches, CSR can be expected to naturally draw employees' psychological changes. Such positive changes in employees would allow them to maintain their well-being and to contribute to the organization by engaging in helping or extra-role behaviors.
Even though academic interest in the micro-effects of CSR has recently increased, understanding of its underlying psychological mechanisms remains insufficient. This study used SIT [18] and the concept of whole self [19,20] to explain why and how perceived CSR can predict employees' OCB by exploring the mediating role of their meaning orientation. Perceived CSR can change employees' attitudes towards pursuing meaning at work. This is because CSR provides workers, who might otherwise be unable to find purpose in their work, with a means of finding fulfillment. Workers who perceive CSR also have a greater sense of pride and self-esteem, which in turn boosts their sense of meaning at work.
This study also contributes to the literature on CSR and grit by examining an individual-level variable as a moderator. In the past, only few studies attempted to determine possible moderators that can strengthen the positive relationship between CSR and OCB. Recently, Oo and colleagues [17] empirically showed that collectivism and person-organization fit can be moderators; however, there is a lack of research on individual-level moderators. In this study, we identified that CSR's positive effects can vary according to grit. Specifically, when gritty people worked at the company with active

Theoretical and Practical Implications
This study contributes to the literature by testing a moderated mediation model of the effect of CSR on employees' OCB. We explored how the positive effect of employee's perceived CSR on OCB was mediated by meaning orientation. We also found that this indirect effect was moderated by individuals' grit levels. To be specific, when gritty people perceived their companies' CSR, they were more likely to pursue meaning, which in turn led them to engage in more OCB.
Our study makes valuable contribution by expanding our understanding about the benefits of CSR for employees. While prior studies on CSR have mostly focused on its macro effects (e.g., financial performance) [2,4,5], our research focused on its micro-effects on employees' attitudes and behaviors. We found that organizations' active engagement in CSR can spur employees to pursue deep meaning in their work and to perform more helping and extra-role behavior. Compared to top-down approaches, CSR can be expected to naturally draw employees' psychological changes. Such positive changes in employees would allow them to maintain their well-being and to contribute to the organization by engaging in helping or extra-role behaviors.
Even though academic interest in the micro-effects of CSR has recently increased, understanding of its underlying psychological mechanisms remains insufficient. This study used SIT [18] and the concept of whole self [19,20] to explain why and how perceived CSR can predict employees' OCB by exploring the mediating role of their meaning orientation. Perceived CSR can change employees' attitudes towards pursuing meaning at work. This is because CSR provides workers, who might otherwise be unable to find purpose in their work, with a means of finding fulfillment. Workers who perceive CSR also have a greater sense of pride and self-esteem, which in turn boosts their sense of meaning at work.
This study also contributes to the literature on CSR and grit by examining an individual-level variable as a moderator. In the past, only few studies attempted to determine possible moderators that can strengthen the positive relationship between CSR and OCB. Recently, Oo and colleagues [17] empirically showed that collectivism and person-organization fit can be moderators; however, there is a lack of research on individual-level moderators. In this study, we identified that CSR's positive effects can vary according to grit. Specifically, when gritty people worked at the company with active CSR activities, they were more likely to pursue a meaning-oriented life and exhibit more OCB in their workplaces. This finding is consistent with Duckworth's [22] claim that gritty people are highly interested in other people's well-being and are able to direct their grit toward other-oriented purposes and goals.
This study also has practical and managerial implications, especially from the perspective of sustainable human resource management. First, it is important for organizations to share information about their CSR activities with their employees actively, as increased awareness of CSR can lead employees to pursue purpose in their work and to engage in more helping and extra-role behaviors. Leaders and managers should pay more attention to employees' levels of understanding and awareness about CSR and help them accurately perceive their organizations' efforts at CSR. Our findings suggested that increasing awareness of CSR not only helps employees to pursue meaning in their work but also helps leaders manage their companies sustainably by encouraging their employees to engage in more helping and extra-role behaviors.
Second, human resources managers and career counselors are recommended to guide clients' career path and improve their organizational culture through intervention programs that support employees' pursuit of meaning. This process is crucial in sustainable management, which requires practices that foster employees' well-being and development [70]. Better understanding of CSR and greater attention to increasing workers' meaning orientation through interventions, such as group seminars and personal counseling, will lead to higher levels of OCB, which can help build individual well-being and career development, while creating a positive work atmosphere and organizational culture. Taken together, we expect that guiding employees based on our results will positively affect the organizations' sustainable management.
Lastly, our results could be applied to an organization's selection process or human resource development programs. According to Schneider's [71] Attraction-Selection-Attrition (ASA) theory, people are likely to be attracted to companies that share their values, personality, and interests; over time, workers who do not fit in well are more likely to leave the organization. In particular, research should pay more attention on the millennial generations (born between 1981 and 2000; [72]), who will become the leaders of the future. This is because Millennials, who are the current and future workers, tend to exhibit considerable sensitivity regarding corporate ethical issues, and their behaviors are more likely to be influenced by CSR [49,73]. To sustainably manage human resources, organizations must prioritize millennial workers' interests in CSR. It is also important for organizations to hire candidates with grit and other-oriented values who respond to CSR activities; alternatively, organizations can educate their current workers to improve these characteristics.

Limitations and Future Directions
This study has several limitations. First, since the data were collected through a self-reported questionnaire, it cannot be free from common method bias [74]. Our CFA results indicated a low probability of common method bias, but future research could produce more objective results by varying the response sources for the independent and dependent variables [74]. Second, this study tried to explain the causal relationship between variables in our model based on a causal step approach [63]. However, cross-sectional research methods are limited in their ability to allow causal inference. Therefore, we anticipate that longitudinal studies will be required to assess the causal relationship between grit and OCB accurately. Third, this study explored the mechanism by which grit, an individual factor, interacts with CSR, an external factor. However, the environmental factors that affect the behavior of individuals with grit in the workplace are expected to vary. Therefore, a study of the settings and environments of various organizations (i.e., organizational culture, atmosphere, and leader-member exchange) would be valuable. Fourth, this study did not take the level of organization's actual CSR engagement into account as the goal of our study was to investigate how individuals' perceived CSR affects their behaviors. However, it is also essential to simultaneously consider the organizations' objective CSR and individuals' perceived CSR. Therefore, case studies or qualitative studies based on workers from one organization are necessary for identifying how congruence or discrepancies between objective and perceived CSR affect individuals' behaviors.

Conclusions
We have attempted to broaden the literature on CSR by studying workers in South Korea. We observed positive micro-effects of CSR on employees' helping and extra-role behaviors in the workplace. Our results showed that perceived CSR was positively associated with individuals' OCB and that this relationship can partly be explained by enhanced meaning orientation. The study contributes to the literature on sustainable business based on CSR, OCB, meaning orientation, and grit. We specifically examined the psychological mechanisms linking CSR to OCB by combining SIT and the concept of whole self. This study has several practical implications as well. Human resources managers should carefully consider and measure employee perceptions of CSR and work on improving them. This study also discussed how corporate counselors and career counselors can guide their employees' career paths and improve their perspectives on the meaningfulness of their work based on our results. Future research based on diverse samples will be required to generalize our results.