A retrospective review of 69 patients with testicular seminoma, stage I and II, treated by orchiectomy and adjuvant irradiation at McGill University Hospitals from 1972 to 1987 was performed. All patients underwent either lymphangiogram or computed axial tomography scan for evaluation of retroperitoneal disease. There were 52 stage I (75%), 13 stage IIA (11%), 2 stage IIB (3%), and 2 stage IIC (Royal Marsden Hospital staging criteria). Median follow-up time was 6.2 years. The 10-year actuarial survivals were 94% and 93% for stages I and II, respectively. Only two stage I patients failed treatment, and both died from metastatic disease. Interestingly, both developed biopsy-proven metastatic brain disease and had no evidence of intra-abdominal recurrence. In stage II disease, only one patient failed the treatment. There was no serious acute toxicity and no late complications have been encountered. Radiation therapy following orchiectomy is the treatment of choice for stage I and for most stage II patients with testicular seminoma. The controversial aspects of radiographic retroperitoneal staging, the use of prophylactic mediastinal irradiation for stage II patients, and the role of surveillance only for stage I patients are discussed.