BACKGROUND: Childhood cancer survivors treated with radiotherapy to a field including the colon or rectum have an elevated risk of developing radiation-induced colorectal cancer (CRC). The Children's Oncology Group recommends colonoscopy every 5 years beginning at age 35 years for at-risk survivors. METHODS: Analyses included 702 five-year survivors (Childhood Cancer Survivor Study) aged ≥36 years who received ≥30 gray of abdominal, pelvic, or spinal radiotherapy. Multivariate generalized linear models were used to calculate relative risks (RR) with 95% confidence intervals (95% CI) for adherence to the Children's Oncology Group's CRC surveillance recommendations. RESULTS: With a median age of 43 years (range, 36-58 years), 29.5% of the survivors (207 of 702 survivors) met surveillance recommendations. In multivariate analyses, age ≥50 years versus age 36 to 49 years (RR, 2.6; 95% CI, 2.0-3.4), reporting a routine cancer follow-up visit within 1 year before the study (RR, 1.5; 95% CI, 1.0-2.2), reporting ≥10 physician visits within the past year versus 0 to 9 visits (RR, 1.4; 95% CI, 1.1-1.7), and discussing future cancer risk with a physician at the time of the most recent follow-up visit (RR, 1.4; 95% CI, 1.1-1.7) were found to be associated with adherence to CRC surveillance recommendations. CONCLUSIONS: Greater than 70% of survivors at an increased risk of CRC were not screened as recommended. Regular physician contact and discussion of screening were associated with a 60% increase in CRC surveillance. Educational interventions targeted at survivors and their primary care physicians are needed to heighten knowledge of CRC risk after radiotherapy and the importance of appropriate surveillance.