Behçet's disease is a relapsing-remitting systemic vasculitis characterized by oral and genital ulcers, uveitis and thrombophlebitis which can involve many organs. Although its pathogenesis is not fully understood, a possible pathogenetic model can be proposed on the basis of recent studies. Genetic factors, in particular, have been investigated and the role of the genes encoding tumor necrosis factor, transporter in antigen processing proteins and MIC (MHC class I chain related) has been emphasized. In addition, a possible polarization of T lymphocytes towards the Th1 phenotype in Behçet's disease has been suggested by recent observations in experimental uveoretinitis and by preliminary data in humans. Neutrophils may also play a role in the pathogenesis of this disease, as they are attracted by macrophage-released cytokines at the site of the lesions, and thus contribute to tissue damage and self-maintenance of inflammation. New strategies for the treatment of Behçet's disease are being devised. In particular, immunosuppressive drugs used in association or in sequence may be administered to patients with particular clinical features or very severe disease.