My thesis explores Sufi narratives of tolerance and non-violence as a theological corrective to violent extremism. It investigates the history of Sufism in Britain, through the cultural contributions of both indigenous and migrant populations. It examines the transnational effort to reform and consolidate divergent Sufi traditions, so as to claim space within the evolving and contested ground of British Islam. I argue that the vast intellectual heritage of tasawwuf offers invaluable tools for building more cohesive societies. By exploring existing efforts and drawing together Sufi interpretations of key Islamic themes and narratives, I will demonstrate Sufism's potential to offer a rigorous, theological challenge to violent Islamist extremism.