The formyl peptide receptor family, FPR1, FPR2 and FPR3 (formerly FPR, FPRL1 and FPRL2 respectively) are Gi protein-coupled receptors that are expressed mainly by mammalian phagocytic leukocytes and found at lower expression levels on endothelial cells, neurons, astrocytes and hepatocytes. Formyl peptide receptors are involved in antibacterial host defence and inflammation. Activation of FPRs mediates induction of neutrophil chemotaxis, production of reactive oxygen species (ROS) to clear damaged cells and stimulation of degranulation of neutrophils. In addition, FPRs have a role in neutrophil transcriptional regulation and cytokine production, and induce neutrophil apoptosis in a ROS-dependent manner. Recently, FPRs have been implicated in the pathogenesis of amyloidosis, Alzheimer"s disease, prion diseases and HIV. Ligand diversity is a prominent and unusual feature of FPR family receptors, suggesting that these receptors may have more complex functions than are currently appreciated. The human genes encoding FPR1, FPR2 and FPR3 are clustered on chromosome 19q13.3-13.4.