Melanocytes are the target of destructive immune responses in vitiligo, which reside in basal (lower) epidermis. IFN-γ expression recruits a superficial T cell infiltration at the dermal-epidermal junction, which is accessible by topical treatments and narrow band ultraviolet B (nbUVB) phototherapy. The bulk of T cell infiltration in alopecia areata, however, occurs in and around the hair bulb, which is deep within the dermis. Treatment modalities for alopecia areata must therefore be able to effectively penetrate the skin. Systemic treatment could be similarly effective for both diseases. nbUVB, narrowband ultraviolet B; UVA, ultraviolet A.