• In recent years, specialized camping programs for chronically ill children, members of their family, or both have proliferated. Although these programs are popular, little systematic evaluation of risk-benefit has been undertaken. In a naturalistic study we evaluated the effect of a 5-day residential camping program to determine the effect of the program on the level of medical knowledge, on the perceptions of how the cancer experience affected the individual, and on the participant's mood state. Analyses of questionnaire data from 90 campers before and after their participation in the program revealed that desirable changes occurred in each of these areas and were sustained for at least 3 months after the program. Siblings reported by parents to have behavioral problems with onset since the diagnosis of the cancer seemed to benefit particularly from this type of program. No substantial negative effects were found regardless of the camper age, adaptational status, or previous camp experience.