Symptoms of repetitive, obsessive and compulsive behaviour were explored in a group of adolescents and young adults with Asperger syndrome and compared to a typically developing group. By means of self-evaluations and an interview regarding such symptoms with the adolescents and young adults and parental evaluations, the parents retrospectively assessed the behaviour of their children from preschool years to middle teens, and the young participants assessed their own behaviour from school years until present time. An anxiety scale was also used. The results revealed no significant differences between the groups on the interview and the anxiety scale. There were, however, significant differences on both the parental and the self-evaluations. Thus, the parents reported that their children had difficulties with repetitive, obsessive-compulsive behaviour, and social interaction from preschool years, and both the parents and the adolescents and young adults reported considerable difficulties in those areas during school years. When comparing the evaluations from the parents and the young participants it was shown that the parents in the Asperger group reported significantly more problems than their children while in the comparison group the parents reported less problems than their children. (Contains 1 figure and 5 tables.)