Early diagnosis of psoriatic arthritis is of importance because an erosive disease is already detectable after a 2-year duration of symptoms. Often psoriatic arthritis cannot easily be detected because of the diversity of disease manifestations in early stages. As up to 30% of psoriasis patients develop psoriatic arthritis an interdisciplinary dermatologic/rheumatologic approach to diagnose findings and treatment decisions would be desirable. Screening tools, such as validated questionnaires allow an early detection and selection of patients with a high probability of psoriatic arthritis even in dermatological care or on a house physician basis. The implementation of the CASPAR criteria as a classification tool for psoriatic arthritis has also improved the diagnosis finding in patients with a recent onset of active musculoskeletal disease. Data from early psoriatic arthritis cohorts illustrate that drug-free remission is rare. An adequate treatment is of importance. The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) has developed treatment recommendations based on the available evidence for different treatment modalities.