Co-management has been adopted internationally within fisheries, bringing resource users into management decision-making and action with government and other actors. Research into how success of co-management arrangements can be encouraged has identified a plethora of factors, such as leadership, enabling policy and legislation and clearly defined boundaries of co-management structures and locations. Such research reflects findings within wider literature on success factors for natural resource governance, including Ostrom’s ‘design principles’. Little attention has been paid, however, to how the wider political and economic context affects co-management specifically and governance of renewable natural resources more generally. Drawing on data from interviews with a range of fisheries stakeholders in Kenya, Tanzania and Uganda, and on secondary sources, the article identifies how the wider political economy is reflected in, and influences, co-management, undermining the potential for success on Lake Victoria. The analysis shows how the political context of competitive authoritarianism in the three countries provides an environment for political interference, constrained resources to decentralized government, insufficient economic growth to offer viable alternative employment to fisheries and endemic corruption. The political economies of the three countries produce a constrained environment in which co-management operates, generating significant challenges to delivering on successful outcomes. The analysis demonstrates the relevance of the political and economic context to natural resource governance and how understanding of the political economy could inform governance design, practice and reform.