This grounded theory study was designed to generate a mid-range theory of treatment from the perspective of boys who have molested children and undergone outpatient treatment. Data included information from seven boys' charts, their written responses to open-ended questions, and audio-taped interviews. The interviews generated a series of statements reflecting the boys' experiences in treatment, which were analysed by the constant comparative method. The basic social process of treatment was 'becoming a success story'. The structural elements of becoming a success story included relapse prevention, compliance and decision-making. The boys integrated these structural elements by talking to people they trusted, listening to what people said, and using what people said to help them do what was right. Becoming a success story took place in a context of family and community support. In its current form, this theory of treatment success can be used in practice to monitor progress through treatment.