Microneedles provide an artificial pathway across the skin barrier for medical and cosmetic applications. This technology has seen a significant increase in popularity over the past years; as an example, the use of multiple small needles mounted on a roller to pierce the skin, prompting it to stimulate collagen production, has undergone a resurgence of interest as an adjunctive procedure for a number of skin disorders. This monograph draws together what is known about how to integrate microneedle technology into clinical dermatologic practice.