Psoriasis is a chronic, systemic, inflammatory skin condition that manifests predominantly as well-demarcated, erythematous, scaly plaques on the elbows, knees, and scalp. While mild cases (minimal body surface) often respond to various topical treatments and light therapy, patients with extensive disease (larger body surface and possibly joint involvement) may require systemic medications for remission. The development of biological agents provides dermatologists valuable ways to help treat psoriatic disease quite efficiently, but literature regarding the monitoring of patients on biological treatments is sparse. Clinical practice varies widely since there is modest strong evidence to recommend or refute most tests currently recommended by the United States Food and Drug Administration. The purpose of this article is to present a practical approach to monitoring patients on biological therapy based on the most up-to-date literature.