This chapter argues that faith-based organizations (FBO) come in many institutional forms and deploy faith-based or religious values in different ways in the context of international development. Since the 1990s, FBOs active in the promotion of international development have benefitted from a revision or erosion of the secularist policies of multilateral organizations and of the Western governments which provide much of their funding. The chapter describes the rise of conservative nationalism and the contributory role of strident religious discourses before considering the implications for organizations most closely associated with the 'faith and development' interface. It also explores some of the distinct challenges for official development agencies and for FBOs arising from the emergence of a post-liberal world. The chapter also explores variations in the role of FBOs as mediators or polarizers through reference to their own characteristics and mandates and through an exploration of the wider and changing political environment in which they operate.