Behçet's disease (BD) is a multisystem vasculitis of unknown origin. In this retrospective study we analyzed the therapy of 32 patients seen between 1978 and 1993 at the Departments of Rheumatology, Ophthalmology, and Dermatology of the Tübingen University Clinic. The aim of this study was to evaluate the efficacy of different therapeutic strategies concerning different organ manifestations of the disease, especially eye disease. A total of 20 patients had cutaneous manifestations or arthritis. Whereas treatment with colchicine (Col), azathioprine (AZA), cyclosporine (CSA), or steroids (Ster) produced only partial remissions, a combination of CSA, AZA, and steroids led to complete remissions. Interferon-gamma (IFN-gamma) therapy led to remission rates of 60% (complete) and 20% (partial). In all, 22 patients had uveitis (posterior or panuveitis). Steroids were effective in only 50% of the patients and Col was partially effective in 66%. AZA induced a remission in 71% of cases and CSA was partial effective in 60%. The threshold combination of AZA, CSA, and Ster induced a complete remission in 66% of the patients. IFN-gamma was ineffective in 80%. IFN-alpha was used in one patient only and induced a complete remission. These results demonstrate that although our patient group is too small to allow significant conclusions to be drawn, in terms of the literature, for mucocutaneous disease and arthritis, IFNs might be the best therapy, whereas for uveitis as well as other more severe features of the disease, CSA or AZA + Ster should be used. If the latter are ineffective, the threefold combination (AZA, CSA, Ster) is probably the most effective alternative. The significance of IFN-alpha will be evaluated in further studies.