The authors review the visual prognosis of 44 patients with Behçet's disease referred to the Ophthalmology and Rheumatology Departments (Hospital S. João-one of the two major referral centers in Northern Portugal), due to ocular complaints or for routine examination, in the last ten years. All fulfilled the clinical criteria for diagnosis of Behçet's disease. Twenty-six were male and 18 female, with mean age 37 years (range 23-66). The mean evolution time since the first clinical manifestations was ten years (range 1-21). Aphthous stomatitis (100%) and genital ulcers (77.3%) were the initial manifestations preceding eye involvement. HLA-B(51)(5) was present in 27 of 36 typed patients (75%). Ocular manifestations were present in 33 patients (75%)-22 patients with panuveitis, eight with hypopyon, four with chronic anterior uveitis and three with episcleritis. Mean age of onset of ocular complications was 32 years (range 20-54). Retinal vaso-occlusive vasculitis was diagnosed in 26 patients (22 with panuveitis and four with posterior uveitis). To prevent ocular relapses, all needed immunosuppression with corticosteroids (drops, depo or systemic), combined with cyclosporine A (CsA) (5 mg/kg/day) in 13 patients and with chlorambucil or cyclophosphamide in six patients, when sight threatening uveitis had previously been refractory to treatment with systemic steroids. The 13 patients under CsA were observed for a period ranging from eight months to five years. Lowdose CsA was found to abrogate the intraocular inflammation, was well tolerated and had no major adverse effects. Regardless of the type of treatment, 21% (14/66) of the eyes lost useful vision five to ten years after initial diagnosis.