Improvements in the treatment of the cancers occurring among children and adolescents have resulted in a large number of patients achieving long-term survival. Treatment-related factors have been shown to have an impact on subsequent health status and quality of life, although there are limited data on survivors who are now 2 or more decades past treatment. The Childhood Cancer Survivor Study (CCSS) was established as a resource for investigating the long-term outcomes of a cohort of 5-year survivors of pediatric and adolescent cancer, who were diagnosed between 1970 and 1986. The CCSS consists of more than 14,000 active participants, including survivors of leukemia, brain tumors, Hodgkin's disease, non-Hodgkin's lymphoma, Wilms' tumor, neuroblastoma, soft-tissue sarcoma, and bone tumors, who have provided self-reported sociodemographicand health-related information. The survivor population has been found to be at increased risk of a broad spectrum of adverse outcomes, such as late mortality, second cancers, pulmonary complications, pregnancy loss, giving birth to offspring with low birth weights, and decreased educational attainment. The ongoing evaluation of large and diverse cohorts of cancer survivors, through resources such as the CCSS, will aid in further identifying high-risk individuals who should be the target of innovative intervention strategies.