Microfinance institutions face a double bottom-line: financial sustainability and outreach to the poor. The objective of this paper is an assessment of the financial and social performance of village banks of the MC² (Mutuelles Communautaires de Croissance) network in Cameroon and guidance to both top and local managers helping them in their decision-making process in order to perform without trade-off between their double objective, i.e., to achieve their social mission in a sustainable manner. An analysis framework in three phases is developed. First, Data Envelopment Analysis (DEA) models are implemented for measuring efficiency, identifying best-practices, and setting benchmarking goals to less efficient MFIs. Then, a DEA operating frontier (DEA-OF) is designed to identify improvement paths, setting short-term goals towards their long-term target. Finally, DEA results are translated into indicators daily used by managers of village banks to provide them effective guidance in developing actions in accordance with their mission.