have extensive training and experience in the diagnosis and treatment of acne, hair loss, psoriasis, and skin cancer for pediatric and adult patients. They also treat benign and malignant skin cancers, melanomas, moles, and other tumors of the skin, contact dermatitis and other allergic and non-allergic disorders and in the recognition of the skin manifestations of systemic (including internal malignancy), infectious diseases, and also benign and malignant disorders of the skin, mouth, external genitalia, hair and nails, and a number of sexually transmitted diseases.