The success of Islamic-based political and economic movements is contrasted with lowerrates of political and economic activity in Muslim countries. The latter -- a significant “participation gap“ -- holds even after accounting for differences at the national-level and, within countries, across individuals. Based on these two trends, the argument is made that Islamic-based movements enjoy a comparative advantage when it comes to mobilizing individuals to participate in collective political and economic activities. This helps to clarify two key research questions: What are the obstacles to political and economic participation among individuals in the Muslim world? And how do references to Islam help to address these obstacles? Three existing explanations for the Islamic advantage are reviewed, each defined in terms of how it sees the obstacle to participation and the role of Islam in alleviating it. While grievance theory holds that Islam speaks to frustrations and resentments among the poor, the faith-based theory of transvaluation argues that religious beliefs create a sense of duty to serve God, regardless of the risks involved. A final theory suggests that individuals are better informed about what they canexpect from Islamic-based groups,.