Laser technology has considerably expanded therapeutic modalities in dermatology and aesthetic medicine. In addition, lasers have broadened the spectrum of diagnostic and therapeutic options in many other medical fields. Dermatologists, especially Dr. Leon Goldman, played an important role in the evolution and use of medical lasers. There was a long way from the concept of stimulated emission as the fundamental idea of laser technology by Albert Einstein in 1917 to the practical use of the laser today. We review the development of laser technology from the early days through the latest advances.

The Q-switched ruby- and Q-switched Nd:YAG-lasers are a therapeutic modality for pigment fanning with high efficiency and low rate of side effects. Attempts of explanation for pigment spread after tattoos are given, but further histological and electron microscopical investigations are needed to find the pathogenetic mechanism.