Gallium nitrate was evaluated by the Southwest Oncology Group in 38 patients with malignant lymphoma, both Hodgkin's disease and non-Hodgkin's lymphoma. Treatment was administered every 2 weeks at a dose of 700 mg/m2, with acceptable toxicity. Seven partial responses (18%) with a duration of 3-11 months were seen: one of seven in Hodgkin's disease and six of 26 in diffuse non-Hodgkin's lymphoma. No responses were noted in nodular types. Gallium nitrate has activity in lymphomas and should be combined with more active drugs for patients who have undergone less intensive prior therapy.