One of the largest Islamic movements of contemporary times, in terms of both geographical spread and number of activists, the Tablighi Jamaat (TJ) has received but scant attention from scholars. By and large, what little has been written about it has focused on the movement in its South Asian setting. To date no detailed study has been conducted on the TJ in the West, where it has become increasingly active in recent decades. This paper seeks to study the origins and growth of the TJ in one such Western country—Britain, starting from the 1940s continuing till the present day. The paper begins with a brief account of the growth of Muslim communities, largely of South Asian origin, in Britain and this provides the context for the study of the TJ in the country. It goes on to discuss the growing appeal of the TJ to these early migrants, seeing this as reflecting the concerns and needs of groups who found themselves culturally uprooted in an alien land. The attraction that the TJ held was not, however, uniform across these Muslim groups, and here we deal with the movement’s special appeal among certain classes and ethnic clusters among Britain’s Muslim communities of South Asian origin. Tracing the historical development of the TJ in Britain through the decades, we finally turn to the state of the movement in the country today. Here we focus on how the movement is faring among young British Muslims and search for answers to the question of why it appears to be facing a crisis of credibility, with young Muslims increasingly turning either the secular way or going in for more activist, and sometimes more aggressive, Islamic groups.