Within the space of the last 5 years, application of the revolutionary in vitro method of deoxyribonucleic acid (DNA) amplification known as the polymerase chain reaction (PCR), has become ubiquitous. The rapidly increasing number of clinical and research articles utilizing this technology, both in the dermatologic and general medical literature, requires one to have at least a basic understanding of how the PCR is conducted, what it has to offer, and the potential shortcomings. Such knowledge will hopefully allow a more critical appraisal of an increasingly complex literature. This review aims to describe the methodology and medical applications of this powerful technique with special consideration to the increasing role PCR may have on dermatologic research and practice.