The Childhood Cancer Survivor Study (CCSS), a multi-institutional, multi-disciplinary collaborative research resource, was established to systematically evaluate long-term outcomes among childhood cancer patients who survived five or more years from diagnosis. The CCSS, which includes banked biospecimens, detailed information on cancer diagnosis, treatment-related exposures, and outcomes, is the largest comprehensive resource available to facilitate the long-term study of pediatric cancer survivors. Recruitment of the initial cohort, consisting of survivors of specific cancers diagnosed prior to 21 years of age between 1970 and 1986 and a cohort of siblings of survivors, began in 1994, In 2008, expansion of the cohort with five-year survivors diagnosed between 1987 and 1999 was initiated. When expansion is complete, the combined cohort will include more than 37,750 eligible survivors with detailed treatment exposure information available for investigation of late mortality. Among the eligible cohort, an estimated 26,000 to 27,000 active survivor participants will contribute detailed health-related and quality of life outcomes. Extensive use of the CCSS resource by the research community has resulted in: 160 published and in press manuscripts; 143 abstracts/presentations; 29 investigator-initiated grants (totaling approximately $24.7 million); formal training of 31 students/new investigators; 17 molecular genetics investigations; the conduct of 4 randomized intervention trials; increased knowledge to inform exposure-based clinical follow-up guidelines; and, a highly successful model for multiple international initiativs of pediatric cancer survivorship research. During the next five years, activities will focus on maintaining, enhancing, and maximizing use of this singular resource. The overarching goal of the CCSS resource is to increase the conduct of innovative and high impact research related to pediatric cancer survivorship.