As survival time has been extended for young cancer patients, their informational needs have also increased. Using written questionnaires, we surveyed 63 adolescent patients, 60 parents, and 53 physicians to compare their perceptions of patient-communication patterns and current and preferred information sources. Physicians were the main current and preferred information sources noted by all three groups. Group discussions with patients the same age, films and television programs, and books were ranked as acceptable but less preferable sources by more than half of each group. More than 90% of the patients were usually accompanied by a parent. Patients most frequently sought their parents to discuss general concerns and cited parents as their second most frequently used source of disease-related information. Adolescents qualified their parental discussions more than was perceived by their parents (P less than 0.01) and viewed themselves as discussion initiators more frequently than did their parents (P less than 0.05). Parents were more likely than patients to prefer physicians as their child's information source (P less than 0.05). Physicians consistently underestimated their own and the parents' importance, believing instead that the patients relied more on peers. Fewer physicians than patients or parents favored including parents in discussion with health professionals (P less than 0.001).