The fragmentation of rebel groups has received extensive attention from scholars and policy-makers alike. Fragmentation has been linked to an increase in civilian deaths, prolonged conflicts, and difficult peace negotiations. Despite the deliberation given to this field, this study argues that rebel governance serves as an explanatory variable that has been overlooked in the literature. This study aims to close this research gap by examining the influence of rebel governance on rebel fragmentation. The thesis suggests that rebel governance intervenes with the opportunity for rebel lieutenants to find the support of networks to create a splinter, and is successful in preventing rebel lieutenants from forming potential splinters. Therefore, it is hypothesized that rebel governance reduces the likelihood of rebel fragmentation. Using data on rebel groups active between 1946-2012, this thesis finds quantitative evidence in support of the hypothesis across all models. Furthermore, support is found that suggests that the more rebel institutions are present, the less likely it is that the rebel group fragments. Additionally, this study employs a survival model of which the results suggest that rebel groups who employ governance take longer to fragment compared to rebel groups without governance.