Biologic agents, or protein-based drugs derived from living cells, are becoming commonplace in dermatology for the treatment of psoriasis, but their use spans many dermatologic conditions beyond psoriasis and psoriatic arthritis. In recent years, there has been considerable interest in their use for other inflammatory skin diseases. This article will review currently available data and reports on the off-label use of biologics in the treatment of cutaneous diseases other than psoriasis, including inflammatory dermal processes, autoimmune bullous skin diseases, connective-tissue diseases, and hidradenitis suppurativa (HS).