Abstract
Karl Gustav Theodor Simon is considered as the founder of dermatopathology, because for the first time in modern times he beds the bases of the microscopical examination of the cutaneous diseases. He worked in Berlin as a private physician, general practitioner, especially for the poor patients, continuing his research in pathology and focusing on the cutaneous diseases, in which the use of the microscope had a central role. During his medical career, he achieved to be acknowledged as one of the most important figures in the treatment of cutaneous diseases and to be included among the best dermatologists and venerologists at the time worldwide.