RecruitingBiological interventionSwiss Dermatology Network of Targeted Therapies (SDNTT)The purpose of this study is to evaluate the long-term course of patients with psoriasis and psoriatic-arthritis in systemic treatments such as, methotrexate, cyclosporin A, fumaric acids, acitretin, systemic PUVA, etanercept, infliximab, adalimumab and ustekinumab. A patient will be included at first initiation of the treatment and will remain in the registry for 10 years, regardless of subsequent therapy. The registry will also evaluate safety clinical outcomes and health related quality of life.