This document provides a guide for USAID staff and partners on designing programs to reform capture fisheries and aquaculture sectors. It aims to ensure environmental sustainability, economic profitability, and social responsibility. The guide emphasizes reducing threats to biodiversity and ecosystem productivity through improved governance and more integrated management practices. Well-designed programs can reform fisheries and aquaculture to reduce environmental and social impacts while increasing productivity, incomes, and livelihoods. The guide addresses key questions on how to design, implement, and evaluate responsible fisheries and aquaculture programs.