Psoriasis is one of the most common skin diseases. A variety of molecular alterations has been identified in the active, lesional epidermis and dermis of psoriasis, but the pathogenesis still remains unexplained. Therefore, all antipsoriatic therapeutic regimens are symptomatic. Although there is no cure for psoriasis, a variety of therapeutic modalities is available to reduce the severity and increase the life quality of the patient. In cases with mild to moderate psoriasis, topical therapy (tars, dithranol, topical corticosteroids, and vitamin D derivatives) is the most appropriate choice for initial treatment. For patients with more severe, recalcitrant psoriasis, application of UV-radiation and systemic therapies (e.g. retinoids, methotrexate, cyclosporine A) are available. These modalities are more effective than topical therapy but they are also associated with significant cutaneous and/or systemic adverse effects and a risk-benefit ratio must be taken into account. In recent years, a variety of new approaches and substances has been developed. Their efficacy and safety should be proven in the future.