Over a ten year period, 71 cases of malignant non-Hodgkin's lymphomas were treated at the Department of Internal Medicine, Nordland Central Hospital. Of these cases, 41 were low grade malignant non-Hodgkin's lymphomas, while 28 were high grade. 41% presented localized disease. 30% had primary extranodal manifestations. Median age was 68 years. 5-years disease-specific survival was 57%. The results of treatment are judged to be satisfactory when compared with the results from other unselected materials. Improvements can be made on some points. The study revealed possibly too extensive use of surgery in patients with extranodal manifestations, and too extensive use of aggressive chemotherapy in patients with low grade malignancy.