Cord compression was noted in 26 patients with extradural malignant lymphoma. There were 19 cases of nonHodgkin's lymphoma and seven cases of Hodgkin's disease. Eighteen cases of non-Hodgkin's lymphoma had intermediate or high grade malignancy types according to the Working Formulation Lymphoma Classification. These patients represented 28% of all extradural malignant tumours seen at the Royal Adelaide Hospital (RAH) and 2.5% of all patients with malignant lymphoma, during an 11 year period. The patients were classified in three presenting groups: Group A, six patients with primary extranodal extradural lymphoma; Group B, nine patients with both extradural lymphoma and disseminated disease at initial presentation; and Group C, 11 patients who developed extradural lymphoma during the course of established disease. Only classification by groups appeared to affect survival time. Group A had the most favourable prognosis, with a 5 year survival of 83%. Five of the Group A patients had a relapse of lymphoma; four at distant sites and one in the retroperitoneum. Laminectomy was essential to provide a diagnosis in Group A patients. The most useful warning symptom of impending spinal cord compression was back and/or radicular pain, which preceded neurological deficit either by days or by up to 5 years. Plain spinal X-rays were abnormal in 64% of cases, emphasizing the value of this simple procedure.