Elucidation of the immunopathogenesis of psoriasis has led to the discovery of novel biologic agents for the treatment of moderate-to-severe plaque psoriasis. There are currently five biologic agents approved by the US Food and Drug Administration for psoriasis which have proven to be quite efficacious in clinical trials and in post-marketing and clinical experience. As more details are uncovered about the immunologic pathways involved in initiation and maintenance of this disease, there will be an increasing development and marketing of novel therapeutics. It is crucial to understand the immunopathogenesis of psoriasis and the mechanisms of these novel agents in order to to treat the psoriatic population effectively and mitigate disease burden. This article reviews the currently approved biologics for the treatment of psoriasis, with emphasis on efficacy and safety. There are countless therapies currently in the research pipeline, with mechanisms ranging from receptor antagonism to signal transduction pathway inhibition. The initial trials and future studies involving these new agents are also reviewed. As therapeutics escalate through the research pipeline, the management and treatment of psoriasis will likely become more manageable for practitioners and patients.