This study provides a qualitative analysis of an Assembly of God Pentecostal church in the North East of England. The research employed an ethnographic framework incorporating overt participant observation and in-depth interviews over the period of one year at the City Christian Centre. In addition, a number of other churches (of varying denominations) were visited and observed. In this work, former interpretations within the sociology of religion, regarding membership and recruitment, are challenged and new perspectives offered. Few ethnographic studies of conservative evangelical Christians in the United Kingdom exist and quantitative work on this group, generally, has failed to define significant concepts such as salvation and conversion adequately. While such concepts remain foundational to the conservative evangelical believer, a significant transformation of religious expression is taking place within contemporary British Pentecostalism. This thesis gives an account of a synthesis between classical Pentecostals and the Charismatic movement that is creating a distinct form of spiritual expression resulting in a hybrid church. This fusion of traditions affects congregations in a number of important areas. Expressions of praise and worship, theological interpretations and church leadership each reflect the dynamics of the hybrid church. So in addition, does a shift in class composition. Once the preserve of the working classes, Pentecostalism in Britain is now much more socially and economically diverse in its membership. This thesis comes at an interesting time for the sociology of religion. Much is said about a resurgence of interest in religion, this is partly due to its persistence in society. Much work has focused on church demographics and secularisation, this work, however, shifts the emphasis away from religious decline to religious adaptation and change.