In 1927 Emil Kraepelin updated his pre-War textbook Klinische Psychiatrie, highlighting the impact of cocaine on the mental health services of that era. In 2007 Pat McFadden, the Minister for Social Exclusion, discussed the cost of ‘chaotic’ people, defined by Baker & Velleman as those mentally ill who also have substance use disorders, to public services. He suggested that such a person will cost public services around £500 000 over the period of ten years, and there are an estimated 6400 chaotic people in London alone. With ever wider and more diverse substance use now than 80 years ago, the complex needs of people with dual diagnosis will present an increasing challenge to both clinical and social care.

I began to read Baker's & Velleman's Handbook with excitement that evidence-based management, based on a deepening understanding of life with complex disorders, would be taken far beyond routine clinical practice. To begin with the good news, several of the 40 contributors to this 20-chapter book write with vividness and literary ease. The Journal's readers may already be familiar with the eminently readable works of Hubert Lacey or Ilana Crome. Smith & Velleman's chapter on family interventions is a model of concise, informative and practical information and the family nursing case study rings of truth.

However, the more I read this hefty handbook, the more I felt it failed in its aim to ‘substantially improve’ the ‘quality of treatment’. I had hoped I would learn about various assessment scales/algorithms, but these were mostly introduced sketchily and uncritically.

The book seriously lacks neuroscience or genetics in conceptualisation, and a surprisingly limited amount of clinical guidance is provided on prescribing or toxicology. In identifying problem-areas there is very little about lifecourse approaches that might illuminate, for example, the complex relationship in women between traumatic experiences early in life (e.g. childhood sexual abuse or bereavement) and chemical dependence, or might unravel the multi-factorial interaction between mid-life alcohol misuse and senile dementia. The historic lessons of barbiturate use in the period before suicide are also missing. I personally find the chapter on anxiety as the most disappointing. Particular studies are absent, for instance on individuals with overlapping cocaine rituals and obsessive–compulsive disorder, or on patients whose nocturnal panic follows alcohol nightcaps. A much more serious lack of insight concerns therapeutic addicts. Admittedly, dependence on benzodiazepines is mentioned here, but there is no discussion of the interaction between clinicians and patients with chronic anxiety that might produce this dependence. ‘Big Pharma’ has almost expunged the term ‘benzodiazepine dementia’, but when Baker & Velleman state that ‘impairments in cognitive functioning may help to maintain substance use and anxiety’, they could have nevertheless tried to make the connection.

The Handbook can be summarised by a phrase from the chapter on learning disability: ‘there are no empirically validated models and no best practice guidelines in this area’, but it takes the authors a 22-page chapter to arrive at this conclusion. Outcome statistics are rarely discussed in relation to any interventions. For example, therapeutic communities have long been a key treatment option for the most chaotic patients, but it is only briefly mentioned here as ‘promising reports of efficacy’ (p. 312). Instead, Lacey's team give structured ‘day programmes’ in relation to treatment of eating disorders.

The editors finish their Handbook with a quotation from Charles O'Brien. It is a pity they did not consider his ongoing research on day hospitals in their discussion on coexisting cocaine dependence and depression.