Attributions for problem child behaviours and acceptability of behavioural· family intervention were compared in 35 parents of children with attention deficit-hyperactivity disorder (ADHD) and 15 parents of children without behavioural problems. Parents responded to questionnaires and rating scales provided in booklet form on the frequency and severity of his or her child's behaviour, and what he or she believed to be the general causes of the problem behaviour. The results of the present study suggest that severity and frequency of an ADHD child's behaviour may be the major factors influencing parental attributions about the cause of the disorder. Compared with parents of children without behavioural disorders, parents of children with ADHD generally saw biological causes as being more influential on their child's problem behaviour than did the parents of children without ADHD. This difference in beliefs about causation did not, however, generate significant differences between groups in the acceptability of behavioural family intervention.