Systemic and biologic treatments used for the treatment of moderate to severe psoriasis show significant variability in efficacy, are associated with varying degrees of toxicity and, in the case of biologic therapies, are expensive. There is a great need for non-invasive biomarkers to predict treatment outcomes from these therapies and individualize care for psoriasis patients. Identification of pharmacogenetic and pharmacogenomic markers of treatment response may be useful in predicting clinical response to psoriasis therapies and would help in the development of individually tailored treatment. This would increase the cost effectiveness of treatment and reduce unnecessary exposure to treatment toxicity. This review details the current status of pharmacogenetic and pharmacogenomic markers in psoriasis and explores how these research tools may ultimately lead to safer, more directed treatments. Until now, pharmacogenetic studies in psoriasis have been underpowered to produce reliable results, and many have not recorded treatment response or toxicities prospectively in an objective and reproducible manner. Large-scale collaborations and use of patient registries for systemic and biologic treatments in well characterized patient populations that are uniformly treated and systemically evaluated could play a valuable role in advancing the field of pharmacogenetics and pharmacogenomics of psoriasis.