A 40 year old woman presented with a spinal epidural tumour, which on histology was shown to be a plasmacytoma. At that time she had no evidence of multiple myeloma. Ten months later, she developed a second isolated plasmacytoma in the spleen, for which she underwent splenectomy. Two years after her initial presentation she had another recurrence in the liver, followed by a full-blown picture of multiple myeloma. The myeloma was progressive and resistant to all forms of chemotherapy. She finally died of a massive gastrointestinal haemorrhage. The clinical features, natural evolution and management of solitary plasmacytomas are discussed.