The long-term survival of 324 multiple myeloma patients treated with conventional chemotherapy (CT) was analysed after at least 10 years follow-up. The unselected group of myeloma patients < or = 70 years, as representative of the population, was derived from three prospective multicentre trials by the Finnish Leukaemia Group. The median overall survival time (OS) was 49 months. At 10 years, 13% of the patients were alive. The significant single pre-treatment prognostic factors for long-term survival were age, Hb, platelet count, serum-creatinine and proportion of plasma cells in the bone marrow. Staging according to Hb level and plasma cell degree was more useful than that of the Durie and Salmon system in predicting long-term survival. The first-line chemotherapy combination and the level of response were unimportant in this respect. A long plateau phase after first response and response to salvage chemotherapy were important prognostic factors. Not only the salvage regimen but also the whole supportive treatment and adequate control of complications throughout the course of the disease are important.