The study evaluates the long-term course of patients with Pso and PsA in systemic treatments. A patient will be included at first initiation of the treatment and will remain in the registry for 5 years, regardless of subsequent therapy. Nationwide, initially 35 (long-term approx. 50-80) dermatologic practices and hospital ambulances with expertise in systemic and biologic treatment will consecutively enroll patients. Follow-ups will be every 3 months, comprising patient and treatment characteristics, clinical parameters, patient-defined benefit, quality of life and adverse events. Standardized questionnaires will be addressed to the patient and to the dermatologist 12 times at the dermatologic centres. In interim intervals, patients are directly contacted another 9 times by mail.