Psoriatic arthritis is a common inflammatory arthropathy that occurs in approximately 25% of psoriasis patients. Due to significant advances in therapeutics--mainly the advent of biologic therapy--the disease has been subject to intense investigation recently. This review summarizes recent investigations of disease pathogenesis and clinical treatment. Clinical responses to tumor necrosis factor-blocking agents appear robust and superior to traditional disease-modifying drug responses, whereas other interventions, such as costimulation blockade, require more investigation. The pathogenesis of the disease appears related to T helper 17-polarized immune responses that target skin, joints, and the enthesial compartment. Finally, new insights into the disorder's genetic antecedents are emerging as more cohorts of patients undergo advanced genetic screening methods.