"Superficially, Brexit looks quite straightforward; but, dig only a little deeper and the complexities are quickly evident. This is particularly so for the security sector. This book is an important and timely contribution to the debate and to the need for specialists and wider public alike to have steady, informed hands guide them through the maze. The authors take the reader carefully through a phased introduction to these complexities and provide a detailed explanation of the respective legal and agency components of the intelligence/law enforcement sectors. One of the ‘stand-out’ features of this book is that it is able to present the reader with a clear understanding in a straightforward and accessible reader-friendly style of what are highly complex, often highly nuanced elements."