The problems related to proliferative disorders in melanocytes, epidemiological and clinical aspects of melanocytic nevi, and the major risk factors for skin melanoma are discussed. Skin phototype, as well as predisposition to emergence of multiple melanocytic nevi, are genetically determined. However, medical follow-up and following recommendations on protection against exogenous exposure to ultraviolet (UV) radiation (which provokes photoaging and neoplastic processes in the skin) are the optimal measures for preventing malignant melanoma. In actual practice, adherence of patients with multiple nevi to such preventive measures is low, and the use of sunscreens by such patients is often irregular or insufficient.