Forty-three patients with advanced measurable lymphoma, progressive after conventional therapy, were entered into a phase II study of m-AMSA 90-120 mg/m2 every 3 weeks. Five patients were ineligible and response could not be evaluated in four patients. For HD there were two partial responses (14%), lasting 6 and 41 weeks, in 14 evaluable patients. Among 20 evaluable patients with NHDL three (15%) achieved partial remission, but duration of response could not be evaluated. One patient with diffuse histiocytic lymphoma died of infection at 4 weeks, a second with lymphoblastic lymphoma was given high-dose steroids commencing at 6 weeks, and the third patient with nodular poorly differentiated lymphocytic lymphoma refused further treatment after one course. Leucopenia was more marked in patients with NHDL (WBC nadir X 10(9)/l, median 2.2, range 0.2-4.3) than in HD (WBC nadir X 10(9)/l, median 2.8, range 0.85-7.2), as was thrombocytopenia. There was one toxic death and one life-threatening infection, both secondary to myelosuppression. Non-haematological toxicity was mild. m-AMSA has marginal activity in previously treated lymphomas and causes considerable myelosuppression.