Progress in modern medicine is often the result of sophisticated technology that allows us to quietly probe into the deepest regions of the human body or to analyze its actions at the molecular level. A field of medicine is rarely dramatically changed by simple observation. After more than three decades of relative inertia, surgical hair restoration is undergoing such a change. This article discusses the logical applications of these observations to clinical practice, a logic that has literally revolutionized hair transplantation in just a few short years. It will also touch upon some of the illogic judgments that contributed to its delay.