Purpose: Surveillance for long-term complications related to previous cancer therapy can help diagnose/ manage chronic health conditions in childhood cancer survivors and improve survivor quality of life. However, a challenge to delivering long-term care to childhood cancer survivors is loss to follow-up; many patients discontinue care at specialized survivor care centers. The purpose of this study was to examine patterns of loss to follow-up among a cohort of childhood cancer survivors. Methods: This retrospective study examined follow-up patterns among a nonrandom representative sample of 370 childhood cancer survivors among 1116 patients from a single institution. The median age of patients at diagnosis was 10.2 years (range <1-21). Factors potentially related to follow-up were utilized to evaluate patterns of follow-up across 5-year intervals following completion of active therapy. The association between patient characteristics and follow-up was evaluated using univariate and multivariate binomial regression models. Results: The probability of follow-up 1-5 years post-treatment was 91.2% (89.7%-92.5%) but dropped to 68.5% (66.2%-70.8%) during years 6-10, 47.7% (45.0%-50.3%) during years 11-15, and continued to steadily decrease over time. Overall, white race, diagnoses at younger ages, patients with lymphomas/leukemias, and decade of diagnosis were each associated with somewhat better rates of follow-up. Conclusions: These findings highlight the lack of follow-up by adult survivors of childhood cancer with only approximately one-half of patients returning for follow-up 10 years after completion of therapy. Interventions focused on educating both patients and primary care physicians may help to increase long-term follow-up care among this at-risk population.