A pilot study on 35 women was performed to determine the feasibility of giving whole abdominal radiotherapy after surgery and chemotherapy for Stage III and IV ovarian adenocarcinoma. The planned duration of therapy was only 6 months from diagnosis. Chemotherapy consisted of four courses of cis-platinum 100 mg/m2 alternating every 10-12 days with four courses of methotrexate 300 mg/m2 and cyclophosphamide 500 mg/m2 followed by folinic acid rescue. Twenty-nine of 35 (83%) patients were shown at second look surgery after chemotherapy to have residual tumour deposits no more than 2 cm in diameter. The usual radiotherapy dose was 2400 cGy in 20 fractions over approximately 4 to 5 weeks, with kidney shielding, and was generally well tolerated. Three patients failed to complete radiotherapy, two because of progressive disease and one because of persistent nausea and vomiting. During radiotherapy the white blood count fell below 2.0 X 10(9)/litre in seven patients (26%), and in eight patients (30%) the platelet count fell below 75 X 10(9)/litre. However, the white blood count nadir of 1.5 X 10(9)/litre was reached by 1300 cGy and the platelet nadir of 45 X 10(9)/litre was reached by 1400 cGy and both then levelled or recovered despite continuing radiotherapy. The median follow up since diagnosis is 26 months. Four of 12 patients with no tumour detected at second look operation have relapsed compared with 13 of 15 patients who had detectable tumour. Toxicity of this multi-modality therapy was acceptable.