Psoriatic arthritis is a distinct form of inflammatory arthritis associated with psoriasis, which exists in a number of clinical presentations. Although a large number of patients have a mild form of arthritis, there is a population who present with a very aggressive, deforming and disabling arthritis. The prognostic factors for the development of this type of arthritis are unclear as yet. Therefore, PsA may not be as benign a condition as previously thought, and the approach to its management should be similar to that for rheumatoid arthritis. Current investigations are in progress to identify the prognostic factors associated with severe disease in PsA. Until the results of these studies are available, all patients should probably be treated more aggressively, and earlier.