Alopecia can be divided into disorders in which the hair follicle is normal but the cycling of hair growth is abnormal and disorders in which the hair follicle is damaged. Androgenetic alopecia is the most common cause of hair loss in women. Other disorders include alopecia areata, telogen effluvium, cicatricial alopecia, and traumatic alopecias. The diagnosis is usually based on a thorough history and a focused physical examination. In some patients, selected laboratory tests or punch biopsy may be necessary. Topically administered minoxidil is labeled for the treatment of androgenetic alopecia in women. Corticosteroids and other agents are typically used in women with alopecia areata. Telogen effluvium is often a self-limited disorder. Because alopecia can be devastating to women, management should include an assessment for psychologic effects.