Background: Childhood cancer survivors (CCS) are at elevated risk of chronic health conditions. Chemotherapies can cause recurrent acute kidney injury which may progress to kidney fibrosis, chronic kidney disease (CKD) or hypertension (HTN). CCS surviving to adulthood are at ≥3 times the risk (vs. non-CCS) for CKD, HTN and lower quality of life. However, the timing of CKD and HTN onset in CCS completing cancer therapy in childhood remains unclear. Guidelines provide recommendations on managing post-cancer therapy effects in CCS, but they lack specificity on kidney testing content, frequency and complications. This discord is largely due to knowledge gaps on which CCS develop CKD or HTN after cancer therapy, when outcomes occur and their severity. Existing work has shown in select patients, CKD and HTN in CCS likely begins in the first 5 years post-cancer therapy and that the burden is significant. With robust data on CKD and HTN, international CCS follow-up guidelines can be optimized to include detailed and actionable recommendations on kidney and blood pressure monitoring and treatment.