There are two confessions to be made: this book is one I have long wished to write about and my second confession is that I have carried this little text with me these last few weeks, I believe to the annoyance of several colleagues. Grand rounds have never been so much fun. One quick glance at page 280 will allow the reader to confidently enquire whether hexosaminidase deficiency has adequately been excluded, or if Fabry's disease may be a differential diagnosis.

Psychosis is a frequently occurring syndrome and at the heart of what psychiatry is all about. Thus, expertise in assessing patients and coming to this diagnosis is central to the task of the psychiatrist. Cardinal & Bullmore's book deals with the causes of psychosis and proposes a clinical approach to diagnosis.

The first section discusses the full range of organic causes of psychosis including genetic, autoimmune, nutritional and inborn errors of metabolism among others, together with primary psychiatric disease. There are useful tables and summaries. It is brief yet compressive enough for the practising psychiatrist and trainee alike. In the second section, there is a brief guide to history and mental state examination, which should prove useful for the trainee.

There are aspects that could be improved. The authors aim to be comprehensive yet concise; hence some chapters are so brief as to be redundant. This is particularly true of the chapter on delirium. The layout and extensive cross-referencing makes the text, at times, difficult to read. I was also somewhat disappointed that there was no reference to the current debate on categorical v. dimensional classification of psychosis. There will need to be future revisions to this text, with the implementation of ICD-11 and DSM-5, although the latter is to some extent taken into consideration. But I suspect this book will soon be core reading, so future editions will have the opportunity to improve on this first one.

Overall, this small book punches well above its weight. It contains much useful and clinically applicable information as to be a delight for trainees and those working day to day with patients with psychosis. I would wholeheartedly recommend it. I just wish I had written it myself!