The health-related beliefs and behaviors of long-term survivors of childhood cancer are important because of vulnerability to adverse late effects from their primary malignancy and its therapy. A health behavior survey was completed by 110 parents of long-term survivors ranging in age from 11-17 years, and by 40 adult long-term survivors of childhood cancer ranging in age from 18-29 years. The survey included questions on the former patient's frequency of alcohol and tobacco use, as well as diet, exercise, sleep, dental, and seatbelt habits. The reported prevalence of tobacco and alcohol use was less than 10% among those less than 18 years old. Among the adults, tobacco (17.5%) and alcohol (72.5%) use was greater, but problem drinking was infrequently reported. In order to assess their perceived vulnerability, we asked the parents and the young adult patients to rate the strength of their belief that it is more important for the patient to keep healthy compared to most other children or young adults. Contrary to our expectation, demographic factors such as the patient's gender, socioeconomic level, or time elapsed since completion of therapy exerted minimal influence on their responses. Over 80% of parents and 60% of young adult survivors believed that it was more important for the former patient to remain healthy compared to most other people. However, this shared belief in increased vulnerability was inconsistently expressed in the patient's health behaviors. These results suggest that specific changes are needed in the health assessment and education of long-term survivors of childhood cancer.