Abstract
Societies need cooperation that is sustainable. We argue that understanding the mechanisms of sustainable cooperation requires a connection between current analyses of individual interactions and their institutional contexts, and studies of long-term patterns of cooperation at the societal level. We propose a focus on where institutional level arrangements connect with individual level decision making, namely where people interact in families, communities, and organizations, i.e. the "meso-level" of society. Focusing on the impact of external threats, spillover effects and vicious cycles, our transdisciplinary approach highlights the importance of understanding when and how individual and institutional dynamics can undermine cooperation at this intermediate level and what is needed to secure cooperation sustainability in society.