Securing private sector commitment to watershed Rewards for Environmental Services (RES) agreements in Africa is a challenge. This is partially due to the scarcity of downstream beneficiaries, the prevailing policy and institutional arrangements and the internal inefficiencies of some of the businesses. Using the Sasumua case study, we found that the business case based on improving water quality through sediment reduction is weak; the bigger challenge is increasing and maintaining water flows where the most immediate action for companies is not so much upstream land uses, but management and governance of water pipes between the reservoirs and water users. PRESA is currently exploring three avenues for engaging private sector in RES: using the Applied Information Economics approach to re-examine the business case for optimizing decisions for PES in reservoir management; analyzing policy and institutional frameworks for PES; and engaging stakeholders to consider the fund mechanism, disbursing conditional payments for good land use practices.