Why do people join new congregations? How does this happen? And which consequences does this have for people’s belief and behavior? These are the main questions addressed in this comparative case study from the distinctively different contexts of Norway and Thailand. While joining a new congregation in Thailand in most cases is understood in terms of conversion, what happens in the Norwegian context is mainly referred to as a process of revitalized commitment. However, common in both contexts was that joining a new congregation implied an aspect of religious change. In order to understand this change, the author applies perspectives from contemporal conversion studies, such as Lewis R. Rambo’s typology of conversion, and from anthropological studies of change.