In 2005, an Internet-based network for the support of patients with congenital melanocytic nevi in German-speaking countries was started (www.naevus-netzwerk.de). Along with detailed information for patients and parents, the homepage includes a nevus registry which is based on an electronic questionnaire and which aims at providing data on the long-term course of nevi estimated to reach > 10 cm in largest diameter. In the past, congenital melanocytic nevi have been subject to various mythological interpretations (“Tierfellnävus”, lit.“animal coat nevus”; “Muttermal”). Today an increasing body of reliable scientific data allows a differentiated reflection of the risk of malignant transformation and has led to progress in the diagnostic and therapeutic management. Recent findings from the literature and considerations from scientific meetings are reviewed.