Improved survival for pediatric oncology patients is a remarkable achievement of modern medicine. This success can be credited to the introduction of multimodality therapy and newer risk-based therapies developed and tested through national research protocols. With improved survival has come recognition of the many long-term effects of cancer and its treatment, such as vital organ dysfunction, subsequent malignancies, and psychosocial deficits. Childhood cancer survivors are vulnerable to adverse health outcomes which may not become apparent until years after therapy. These events may manifest well into adulthood when these individuals rarely return to their initial cancer center or seek preventive medical care. Risk-based follow-up can offer early detection and/or intervention and provides an opportunity to reduce cancer-related morbidity and mortality. An understanding of the late effects of cancer therapy is increasingly important for the medical community, both generalists and specialists - adult and pediatric, to better care for the growing population of adult survivors of childhood cancer.