The goal of photochemotherapy in psoriasis is to attempt to lower the number of exposures and the total cumulative doses while still maintaining good control of the disease. PUVA has been modified by using better psoralen preparations and more effective light sources, and it also has been combined with other treatment modalities. The objectives in modifying PUVA and combining PUVA with other treatment modalities are to increase efficacy, to reduce short- and long-term adverse effects, and to reduce the cost of treatment. Modalities that have been combined with PUVA include topical corticosteroids, anthralin, calcipotriene ointment, methotrexate, UVB, retinoids, and cyclosporine.