Parental attitude and the parents' perceptions of a child's responsibilities were measured by mailing a questionnaire to 156 parents of cured children of the Pediatric Oncology Center, University of Groningen. Simplistically, the questionnaire concerned parental judgment on (1) the role of the child in decisions about experimental therapy, (2) what information should be related to the child and by whom, (3) parental attitudes toward experimental therapy, and (4) the parents' opinions about ethical aspects of proposing experimental therapy. A high response rate (87.8%) was achieved. A majority of the respondents would allow a child take responsibility in deciding about experimental therapy. In their opinion the median age (16 years) at which a child should be allowed to give consent was higher than the median age (12 years) at which a child should merely be involved in the decision. Parents were more likely to overrule the child's decision if the child decided against experimental therapy than if the child chose the therapy (p less than 0.001). Parents found it more difficult to talk about death than about experimental therapy, and parents would be more willing to involve the physician in discussing experimental therapy than in discussing imminent death with a child (p less than 0.001). Many respondents (68%) felt that the child should be given both altruistic reasons and reasons of self-interest for participating in experimental therapy. About half of all of the respondents believed that a pediatric oncologist should always advise experimental therapy for the benefit of similarly afflicted patients.