In a prospective randomised study 68 patients with limited small cell bronchogenic carcinoma were assigned to induction treatment with combined alternating non-cross-resistant chemotherapy plus split course radiotherapy without (NM) or with (M) subsequent maintenance therapy. Induction chemotherapy consisted of cisplatinum and VP16213q. 3 weeks followed by cyclophosphamide, vincristine and methotrexate (CVM)q. 4 weeks. Three courses of this 7-week chemotherapy programme were given. Radiotherapy to the primary lesion of 25 Gy in 13 fractions was given after each of the first and second courses of chemotherapy. Those in complete remission following the induction phase received prophylactic cranial irradiation. Those assigned to maintenance received a further six cycles of CVM after induction. The overall survival of patients randomised to maintenance therapy was significantly inferior to that of those randomised to no maintenance therapy (median survival NM 19.2 vs M 14.1 months, P = 0.05 log rank). Among patients achieving a complete remission of disease on induction therapy those receiving maintenance also showed a trend towards inferior survival (median survival NM 26.8 vs 18.0 months, P = 0.06 log rank). Deaths in each group of patients were predominantly due to tumour progression. The results do not support the use of maintenance chemotherapy after the use of intensive combined therapy induction programmes in the management of limited small cell bronchogenic carcinoma.