RESUMEN
This article reports a systematic clinical case study of the psychological assessment and treatment of Daniel (9); a coloured South African boy with a diagnosis of attention deficit hyperactivity disorder (ADHD) (inattentive type). The case is of scientific interest because: (1) there was only a single treatment session; in which contingency management training was delivered to Daniel's parents and teacher; (2) there was evidence for the effectiveness of the intervention immediately and at two-year follow-up; (3) it documents the transportability to a South African context of an intervention developed by overseas research; (4) it documents the central role of case formulation in the delivery of effective psychological interventions; and (5) although Daniel met the criteria for ADHD; he also displayed symptoms of depression and social anxiety and the case supports the use of a transdiagnostic approach to case formulation. The conscientiousness with which his parents and teachers applied the programme was a major factor in the effectiveness of the intervention; and such rapid impact would not be possible where parents and teachers are unavailable or not co-operative. The publication of systematic case studies such as this one is important for the development of a local evidence-based practice in South Africa