In humans, the Inhibitor of apoptosis (IAP) family is group of eight proteins that are involved in apoptosis, immunity, inflammation, cell cycle and migration. They all contain the distinguishing baculoviral IAP repeat (BIR) domain, a zinc-binding, 80-amino acid sequence known to mediate protein interactions and, in some cases, bind and inhibit caspases. Some also contain a C-terminal RING domain with ubiquitin ligase activity. XIAP, cIAP1, cIAP2, NAIP, Livin/BIRC7, Survivin, BIRC6 and BIRC8 are the known members of this family. For their roles in cell death and proliferation, IAPs inhibitors are sought after as potential anti-cancer therapies.