Six cases of familial basal cell nevus syndrome encountered over the past 20 years are described. The syndrome is fairly rare and its importance derives from the fact that it is associated with skin lesions of the basal cell epithelioma type that are often highly invasive as well as dysontogenic lesions affecting many organs and systems (mandibular cysts, skeletal anomalies, cerebral calcifications, etc.). On the basis of personal experience and in view of the essentially constant evolution of individual lesions into invasive forms (that were certainly the direct cause of death in two of the six patients), early treatment is considered to be of prophylactic significance. The best treatment is thought to be diathermocoagulation rather than traditional surgery radiation treatment.