Humanity confronts a daunting double challenge in the 21st century: meeting widely-held aspirations for equitable human development while preserving the bio-physical integrity of Earth systems. Extant scientific attempts to quantify futures that address these sustainability challenges are often not comprehensive across environmental and social drivers of global change, or rely on quantification methods that largely exclude deep social, cultural, economic, and technological shifts, leading to a constrained set of possibilities. In search of a broader set of trajectories, we combine three previously separate streams of inquiry: scenario analysis, planetary boundaries, and targets for human development. Our analysis indicates there are plausible, diverse scenarios that remain within Earth’s safe bio-physical operating space and achieve a variety of development targets. However, dramatic social and technological changes are required to avert the social-ecological risks of a conventional development trajectory. One identified narrative, which is predominant in the scenario literature, envisions marginal changes to the social and cultural drivers underlying conventional growth trajectories. As a result, it requires unprecedented levels of international cooperation, alignment of powerful conflicting interests, and political willpower to bend technological change in a sustainable direction. We posit that a more viable and robust scenario might lie in the coupling of transformative social-cultural and technological changes, which set the necessary conditions for a transition to a resilient global future. While clearly a first step, our analysis points to the need for more in-depth exploration of the mechanisms and determinant forces for such unconventional futures.