Ten patients with plasma cell leukaemia (PCL), out of 259 cases of multiple myeloma diagnosed in the Haematology Service of the University Hospital of Barcelona in the last 18 years, are presented. Of the 10 PCL cases, 5 were primary and 5 were secondary. Anaemia and thrombocytopenia, along with massive plasma cell infiltration of the bone marrow, were the most striking findings. Osteolytic lesions were present in 9 of the cases and liver involvement in two. Chemotherapy including vincristine and prednisone was administered to eight patients, associated to alkylating agents (melphalan and/or cyclophosphamide) in six of them. Four of these patients received also adriamycin and BCNU. Two objective responses were achieved, lasting for 10 and 3 months, the remaining six patients failed to respond. The median survival for all the PCL patients was less than one month (ranging between 0.2 and 14 months). None of the secondary PCL patients survived for 2 months after diagnosis. Infection (3 cases of septicaemia and 3 of pneumonia), renal failure (2 cases) and liver insufficiency (1 case) were the causes of death in the nine deceased patients. The therapeutic possibilities for this severe haemopathy are discussed.