Under what conditions do states and insurgents cooperate in providing rebel governance? Scholars have recently started to explore the many ways through which rebel groups provide governance in areas under their control, that is, rebel governance. Less attention has been afforded to understanding how and under what conditions governments and rebel groups collaborate in providing governance in areas under rebel control. Examples from cases as diverse as Burma, Afghanistan, the Philippines, Colombia, Sri Lanka, and Côte d’Ivoire suggest that state-insurgent cooperation in rebel governance is not an isolated phenomenon. This is puzzling because state-insurgent cooperation is costly in the sense that it may alienate hardliners in both parties, undermine the legitimacy-building benefits of governance, and reveal sensitive information to the enemy. This article seeks to start addressing this puzzle by comparing instances of state-insurgent cooperation and noncooperation in rebel governance in Côte d’Ivoire and Sri Lanka. We propose that state-insurgent cooperation is more likely on governance issues that are of great importance to both parties’ constituencies and during times when the level of hostility is relatively low. We further argue that both the state and the rebels can limit the negative consequences of cooperation by engaging in strategic contradiction and by camouflaging their involvement. By analysing instances of cooperation and noncooperation on wartime education and [some other domain] in Côte d’Ivoire and Sri Lanka using original interview and archival data, we contribute to broadening our understanding of civil war and statebuilding by unpacking both why and how governments and rebel groups collaborate on providing rebel governance.