The affective bonds between women that lead to trust and cooperation are recognized as the foundation of microfinance programs for women based on the village savings and loan association (VSLA) model. Nevertheless, there has been little anthropological consideration of how trust operates in such groups: how it is established, under what contexts it is sustained, and the importance of culturally-specific values and norms around mutual support. Through studying the concept of benkadi (cooperation or mutual aid) among Malian women who participate in community savings groups, Deubel and Boyer examine how systems of trust constitute the driving force for Saving for Change (SfC), a large-scale savings group program throughout rural southern Mali, and consider the larger implications for the sustainability of international aid programs focused on gender and development.