Although nearly all arteries are surrounded by perivascular fat, its role in vascular function and disease is clearly understudied. At least one type of perivascular fat, epicardial adipose tissue, appears to be related to both weight and age and tends to express proatherogenic/proinflammatory products in subjects with cardiovascular disease. Perivascular fat may evolve from primordial cells in the adventitia or from circulating precursors migrating through the arterial wall. Once deposited periarterially, adipose tissue may release locally a large number of products, which potentially interact with the arterial wall. Additionally, the authors propose that perivascular fat, per se, may attract circulating monocytes through the release of chemokines such as monocyte chemoattractant protein-1. Some of the macrophages traversing the arterial wall en route to the perivascular fat may be redirected and eventually populate the arterial wall itself, thereby enhancing vascular inflammatory processes and accelerating atherosclerosis.