The internet abounds with promises of ‘miracle cures’ for autism and within the published research literature there are numerous claims and counter-claims for the effectiveness of specific therapies. Systematic evaluations, however, indicate that few treatment programmes have a sound evidence base, and even those interventions that do produce positive findings are not successful for all children. To date, the best researched programmes are those involving intensive, early, home-based intervention, and those with a focus on communication and parent–child interaction. This article assesses the evidence base for some of the better evaluated therapies. There is, as yet, no evidence that any one programme is superior to all others. Indeed, large individual differences in response to intervention suggest that the focus of research now needs to shift to the study of which components of therapy work best for which children and under which conditions.