Alopecia Areata (AA) is a common non-scarring alopecia that usually presents as well circumscribed patches of sudden hair loss that affects 0.1-0.2% of the population. The aetiology is thought to be both genetic and autoimmune in nature. 139 single nucleotide polymorphisms have been identified in 8 regions of the genome and are found to be associated with T cells or the hair follicle. Furthermore, patients with AA have been found to have an increased frequency of hair follicle-specific auto-antibodies. The diagnosis of AA is usually made on clinical grounds, and further investigations are not usually indicated. Intralesional corticosteroids remain the treatment of choice. Systemic steroids are also highly effective; however side effects make them less desirable to both patients and physicians. Other treatment options available include anthralin, minoxidil, topical immunotherapy and these treatments will be discussed further in depth in this chapter. The morbidity of AA is largely psychological; therefore the successful treatment of AA should include focusing on the improvement of the psychological impact of this condition.