A follow-up study has been made of a personal series of 118 cases of patients with scleroderma (progressive systemic sclerosis) followed for periods up to 25 years. These were classified according to the early distribution of skin changes as Type 1 (skin changes in fingers only), 48 cases; Type 2 (skin changes beyond the fingers but mainly in extremities), 47 cases; and Type 3 (diffuse), 19 cases, and atypical, four cases. Eighty per cent of the total series have survived five years, and 68% have survived 10 years. Survival is related to the type of scleroderma, being much better for Types 1 and 2 (acrosclerotic) than for Type 3 (diffuse). Actual compared with expected survival rate was better for younger than for older patients and for females than for males. Although the disease type gives an indication of survival in general, the caution must be used in the individual cases, as the course of the disease is very variable even in patients of the same type, and is subject to remission and relapse.