Autism is not a condition that I have studied and at times I have been concerned that this Journal may have published a disproportionate number of studies on a condition that is relatively rare and primarily determined by genetic factors, and for these reasons, perhaps of less relevance to most clinicians. Having read Pat Howlin's Practitioner Review I realise just how wrong I have been on both counts! Not only are autism, autism spectrum disorders, and Asperger syndrome far more common than I realised (the prevalence estimate of Wing for autism spectrum disorders of just under 1 per 1000 is quoted) but it is also clear that the recent research effort focused on these children has paid dividends in the development of approaches to treatment for the disorders. As Howlin emphasises, these advances have not led to a cure for autism, as claimed by some proponents of therapies such as holding therapy and facilitated communication, and even those producing some change may require an unacceptable burden of commitment for families, for example the home-based behavioural programmes of Lovaas and colleagues. However, as she clearly indicates, we have learned how to guide the management of challenging behaviour and have methods both to enhance communication and to reduce obsessional behaviour in children with autism. A recurrent theme running through this Practitioner Review is the value of early intervention with these children. This, in turn, gives new impetus to both the research concerned with the basic deficits experienced by children with autism and the studies on the detection of early signs of the disorder by, amongst others, Baron-Cohen and colleagues. An example of the former is the paper in this issue by Leevers and Harris into the ability of the child with autism to conceptualise and image “impossible” entities, for example a man with two heads. This study showed that the imagination of children with autism is not as impaired as once thought. Care should be taken not to interpret poor performance on such tests as reflecting lack of creativity or imagination when a problem with understanding the nature of the task or with certain task demands, such as planning, may be responsible.