PURPOSE OF REVIEW: Genetic testing for the presence of germline mutations in cancer-predisposing genes can identify individuals at increased cancer risk. For these individuals, the institution of cancer surveillance measures is recommended with the aim of detecting cancers at early and hence more curable stages. While these principles are well established in adults, they are only entering the pediatric arena. RECENT FINDINGS: The care of children with cancer-predisposing conditions remains a challenge for the practicing clinician. Here, we describe recent findings related to genetic testing and cancer surveillance in three conditions marked by the development of tumors during childhood, including retinoblastoma, Beckwith-Wiedemann syndrome/idiopathic hemihypertrophy and the Wilms' tumor-associated syndromes. We use these conditions to demonstrate how the integration of clinical genetic testing and cancer monitoring has favorably influenced the survival and quality of life for patients. Where possible, we provide evidence-based guidelines for patient management. SUMMARY: Advances in the understanding of cancer predisposition and implementation of standardized cancer surveillance protocols have improved the outcome for certain patients. Future research focusing on enhancing the sensitivity of genetic testing and efficacy of surveillance for at-risk populations could further decrease the morbidity and mortality associated with these conditions.