Religion has been profoundly reconfigured in the age of development. The past half-century has witnessed broad transformations in the understandings and experiences of ‘religion’ across traditions in communities in many parts of the world. This talk will explore some these transformations along the course of deepening entanglements of religious ideas and institutions with the sphere of ‘development’. In particular, it examines case studies from the trans-regional traditions of Buddhism and Islam – with particular attention to new forms of socially engaged practice among ‘development monks’ and lay Buddhist organizations in Thailand, and the implementation of Islamic law within dramatic contexts of interventionist reconstruction in post-conflict/post-disaster Aceh, Indonesia. Both of these cases reveal marked commitments to the establishment of a new, reformed social order. Over the course of these projects, the very idea of religion has come to be re-thought by diverse parties who draw selectively on and dynamically interpret canonical texts and traditions as they engage with a host of other ideas and influences that manifest themselves through contemporary humanitarian and development encounters. Through these two case studies of entanglements, we examine specific ways in which ‘religion’ and ‘development’ interact and mutually inform each other in contemporary Southeast Asia.