Fibrin deposition in rheumatoid arthritis may be responsible for some of the clinical manifestations of the disease. It has been shown that in severe rheumatoid arthritis fibrinolysis is decreased but can be stimulated using the fibrinolytic enhancing agent stanozolol. A prolonged increase in fibrinolysis may decrease joint fibrin deposition and lead to clinical improvement and we have therefore investigated stanozolol as a therapeutic agent. Forty patients were enrolled. Twenty patients received stanozolol 5 mg twice daily for six months and 20 received a matching placebo. Assessment of disease activity was made in the conventional way. Results show that the two groups were comparable. After six months nine of the control patients had withdrawn because of drug ineffectiveness compared with two stanozolol patients, and five control patients felt they had improved compared with 15 stanozolol patients. Disease activity had significantly decreased by the end of the study in the treated group, and detailed analysis showed improvement in ESR, articular index, duration of morning stiffness and visual analogue pain scale. We suggest that stanozolol may be of value in rheumatoid arthritis although this pilot study has looked at only small numbers of patients over a short period.