Psoriasis is a chronic, autoimmune skin disorder that appears to be T-cell mediated. Psoriasis symptoms include erythematous plaques with underlying scaling. Types of psoriasis include psoriasis vulgaris, pustular psoriasis, scalp psoriasis, and psoriatic arthritis. Psoriasis treatment consists of topical agents, phototherapy, and systemic agents. Continued research into the genetics of immune system activation and the discovery of safer, more targeted therapies will help improve the quality of life of patients living with psoriasis.