Hyperandrogenism in women can be caused by various conditions, the most prevalent of which is polycystic ovary syndrome. Common dermatologic manifestations of hyperandrogenism include hirsutism, acne, acanthosis nigricans, and androgenic alopecia. Hirsute women often have increased activity of 5 alpha-reductase, the enzyme that converts the androgen testosterone to its active metabolite, in hair follicles. Likewise, androgens affect the formation of acne by increasing sebum production from sebaceous glands in the skin. The diagnosis of polycystic ovary syndrome includes a complete history, physical examination with emphasis on evidence of androgen excess, and appropriate laboratory investigation to exclude other causes of hyperandrogenism. Treatments for the dermatologic conditions of hyperandrogenism include lifestyle modification, oral contraceptives, antiandrogens, and insulin-sensitizing medications.