Book Review by Dr Peter Grace Didier Bigo, Emma Mc Cluskey, Felix Tréguer (eds), (2024), Intelligence Oversight in Times of Transnational Impunity. Who will Watch the Watchers? Oxon: Routledge. ISBN 9781032406541. 310 pages. This book focuses on two important issues in intelligence oversight: the long-standing acceptance of raison d’état, and the increasing relations between intelligence agencies transnationally and how much those should come under scrutiny and legal restraint. It is not a book that is designed to be read comfortably by intelligence practitioners, and indeed there are priors that suggest practitioners would much prefer it if there was no oversight of their activities at all. Whether framing the enquiry in this way provokes some degree of urgency or simply divides opinion, the questions of raison d’état and transnational oversight are important.