When the body responds to an infectious insult, it initiates an immune response to eliminate the pathogen. The hallmark of the immune response is an inflammatory cascade that can also do extensive damage to host tissues. Inflammation is a major contributing factor to many vascular events, including atherosclerotic plaque development and rupture, aortic aneurysm formation, angiogenesis, and ischemia/reperfusion damage. The immune response is mediated by both circulating and resident leukocytes and the cells with which they interact (e.g., vascular endothelium and smooth muscle cells). The process is orchestrated by the activity of a changing series of released and displayed mediators. These include the expression of adhesion molecules on leukocytes and underlying vascular endothelium and the release of cytokines, chemokines, and tissue‐destructive metalloproteases and reactive oxygen species. This review focuses on the causes, the inflammatory processes involved, and possible strategies for decreasing vascular disease through regulation of the inflammatory response. J. Leukoc. Biol. 67: 591–602; 2000.