Wilms’ tumor is the most frequently occurring renal tumor in children and is one of the most treatment-responsive tumors. A tumor-suppressor gene and other genetic abnormalities have been implicated in its etiology. In addition, patients with several congenital anomalies, such as Beckwith-Wiedemann syndrome, WAGR syndrome, and Denys-Drash syndrome, have an increased risk of Wilms’ tumor. Previously, a three-drug chemotherapy regimen with surgery and radiotherapy was used with patients in all stages. Now, patients with early-stage Wilms’ tumor are treated with a two-drug regimen without radiotherapy, whereas those in advanced stages still receive the three-drug regimen and radiotherapy. Two large collaborative groups – the National Wilms’ Tumor Study Group (NWTS) in the United States and the International Society of Pediatric Oncology (SIOP) in Europe – are involved in Wilms’ tumor management, which differs in some aspects. Multimodality treatment has been used successfully, and in Europe preoperative strategies are used as well. As the survival rate has now reached 90%, the primary objectives of the physician are to perform nephron-sparing surgery in selected cases and to reduce the dosage and duration of chemotherapy and radiotherapy in appropriate cases. Other renal tumors occur rarely, but have also been treated successfully in the last decade.