Dental practitioners are supposed to have some knowledge of skin diseases, particularly those occurring in the face. They should encourage a patient to see his physician or a dermatologist for further evaluation and possible treatment. Diseases of the skin can be classified in various ways. In this overview, diseases are classified as infectious diseases, inflammatory diseases, autoimmune diseases, benign neoplasms, premalignant lesions, and malignant lesions. In the Dutch health care system, family doctors play an important role and, until recently, they have been the obvious persons to whom a patient with a detected skin disease was referred by dental practitioners. The general practitioner then determined whether a referral to a dermatologist was indicated. However, because of changes in the health care system it has become possible for a dentist to refer patients directly to a dermatologist in case of the presence of a skin disease.