Between May 1984 and September 1986, 40 patients with intermediate or high grade non Hodgkin's lymphoma were treated with a novel protocol, which alternated a conventional regimen consisting of cyclophosphamide, doxorubicin, vincristine, bleomycin, and prednisone (CAVBP) with a second chemotherapy regimen, including two drugs with newly discovered activity against lymphomas, such as cis-platin, etoposide, and prednisone (DEP). Twenty-one patients (52.5 per cent) achieved a complete response, 11 patients (27.5 per cent) had a partial response. Eight of the 21 complete responders (38 per cent) relapsed 5 to 24 months after completion of treatment. With a median follow-up of over 40 months, 22 patients are alive, six with disease and three in a second complete response after salvage chemotherapy. Factors negatively associated with response included 'B' symptoms, advanced stage of disease, bulky tumour, poor performance status, number of extranodal sites of disease. 'B' symptoms, bulky tumour, and poor performance status were also negatively associated with survival. Toxicity was modest, with no treatment-related deaths and only six cases of severe leukopenia. The results of this pilot study do not justify comparison of CAVBP/DEP with more efficacious regimens in prospective, randomized trials.