A great deal has changed in the 20 years since the first edition of this book was published. The prison population has more than doubled, the number of secure beds in the UK has increased three-fold, forensic psychiatric practice has diversified and diagnoses such as dangerous and severe personality disorder have come and gone. So John Gunn and Pamela Taylor have provided, they say, a complete rewrite, by new contributors, while retaining credits for all those who contributed to the first edition. With up to 17 credits per chapter, the editorial task must have been daunting.

Furthermore, the boundaries of the specialty, and therefore a book like this, have always defied definition. A pragmatic utilitarianism – we are who we are and we do what we do – is often preferred, the overlapping interfaces with the law, criminology, philosophy, psychology, politics and, of course, other psychiatric specialties remaining blurred. The editors have tried, I think, to be inclusive and there is a wealth of knowledge within these pages. Much of the structure of the first edition is preserved, with added chapters on molecular genetics and neurochemical research as well as clinical topics such as ‘Older people and the criminal justice system’ and ‘Deviant and sick medical staff’. Those chapters with the fewest authors work best, perhaps because the scope is narrower and the authorial voice clearer. Elsewhere it is often hard to know who has written what and occasionally the reader wants to know, because the topics are too nuanced and subject to a range of opinions for the content to be entirely detached from the writer.

This is a multi-author textbook, yet there is a strong editorial voice. A conventional narrative is detectable, giving continuity from the first edition, about the mentally disordered offender as a victim in need of care and treatment, which too often is not forthcoming. I wonder whether for some this will jar with their perception of an incessant creep of service development in the direction of greater security, control and coercion. Since the first edition was published, fewer patients are treated in high security, but the levels of restriction for so many more in medium and low secure care have increased. A greater and more clinical emphasis on the ways in which security can be used therapeutically and its dangers, the importance to risk management of engagement and collaboration, and the therapeutics of subversion, ambivalence and dependence, would have been welcome. The clinical practice of psychiatry in custodial settings also feels relatively underrepresented in the book, given its central importance and the transformation in prison healthcare that has taken place over the past 15 years. The outward-looking perspective, supported by commentaries from around the British Isles and further afield, is especially valuable, as this comparative content is difficult to find elsewhere.

At present there is no other book that provides such a broad and comprehensive reference source for those working in the field. This will be its considerable value for some years to come. I wonder whether we will see a third edition published 20 years from now. With changes in medical training to come and an increasing focus on services rather than professions, psychiatrists may start to define their expertise in ways that do not fit with a general textbook of forensic psychiatry like this. But for now, this will do very well.