The phenomenon of judicialisation in the field of freedom of religion is long recognised. But, to date, little has been written on how advocacy and strategic litigation has actively changed the field. This important books does just that. It shows how Jehovah's Witnesses, Muslims, Sikhs, Evangelicals, Christian conservatives and Russian Orthodox actors have negotiated the right to freedom of religion at the ECtHR over the past 30 years. Drawing on in-depth interviews and case law analysis, and media representation, it is a powerful study of the impact of legal mobilisation on international and transnational law.