Every month we read in the news that too many children are diagnosed with attention deficit hyperactivity disorder (ADHD) and prescribed potentially dangerous medication. Indeed, we have to be careful not to over-diagnose and overtreat our children. The same goes for the new ‘epidemic’ of adults who are emerging with ADHD. As therapists, we are permanently working on this issue by educating health workers and lay people. Nevertheless, we should not forget that the far larger problem is underdiagnosis and misdiagnosis. In physical healthcare nobody would accept underdiagnosis: a large amount of money is spent on screening and prevention of cardiovascular disorders, diabetes, asthma and cancer, for example. We even treat pre- diabetes and pre-hypertension, because prevention is much cheaper than treatment, and the harm to patients and their families can be greatly reduced.