This issue of the Clinics in Laboratory Medicine on "Pharmacogenomics” is being edited by Drs. Roland Valdes and Kristen Reynolds and will cover a wide variety of topics, including but not limited to, fundamentals of pharmacology, a review of pharmacogenetics guidelines, pharmacogenetic testing in pain management, pharmacogenetics of pain management, clinical and economic impact of pharmacogenetic genotyping analysis, exosome analysis in lab medicine, and implementation of pharmacogenetics in developing countries.