Chemokines play an important role in the process of leukocyte recruitment and activation at sites of inflammation. Until recently, the actions of chemokines and the expression of their receptors have only been described on different leukocyte populations. However, increasing evidence has suggested that non-haematopoietic cell types are capable of binding and responding to a number of chemokines. The functional expression of certain chemokine receptors has recently been described on vascular endothelial and smooth muscle cells. These findings provide new insight into the activities of chemokines and indicate that these molecules have a more widespread cellular target than first envisaged. Studies carried out to date indicate that chemokines and their respective receptors play an important role in the regulation of angiogenesis and angiostasis. They may also be involved in developmental and pathological processes such as organ vascularization, embryogenesis and arteriosclerosis.