Chemokines are small heparin-binding proteins that direct the movement of eirculating leukocytes to sites of inflammation or injury.Original studied because of their role in inflammation.Chemokines and their receptors are now known to play a crucial part in directing the movement of mononuclear cells throughout the body,engendering the adaptive immune response and contributing to the pathogenesis of a variety of diseases. Chemokine receptors are some of the most tractable drug targets in the huge battery of molecules that regulate inflammation and immunity.For this reason,clinical trials involving chemokine-receptor antagonists for the treatment of inflammatory conditions have recently began.In this review,we survey the properties of chemokines and their receptors and highlight the roles of these chemoattractants in selected clinical disorders.