Early stage seminoma of the testis has an excellent prognosis when post-orchidectomy para-aortic and ipsilateral pelvic radiotherapy is given. However, studies on testicular lymphangiograms and the rarity of isolated pelvic nodal disease suggest that pelvic radiotherapy is not necessary, except in cases where there is the possibility of altered lymphatic drainage. We report on 27 patients with stage I and IIA seminoma treated between 1983 and 1989. Seventeen patients received radiotherapy to the para-aortic region only. There have been no pelvic recurrences. No long term complications have been encountered. We discuss the reported data which suggest that a reduced complication rate should result from the proposed field reduction. We conclude that irradiating only the para-aortic region in early stage seminoma is logical, should not increase the relapse rate and should reduce the complication rate.