Given the importance of religion to the history of humankind there is comparatively less research in economics on religion and institutions than might have been expected. This chapter explores the channels through which religion affects institutions; key themes in the economics of religion; theoretical frameworks for the study of religion; the relationship between religion and economic growth; the role of the state and its consequences for religious freedom; and social practices. This chapter argues that while there are established theoretical frameworks in economics for examining religion, more research is urgently needed on the interactions between religion and economic growth, and how the state may influence and interact with religious organizations. This role extends to political institutions and social practices associated with religious matters.