Atherosclerosis is a chronic lipid-driven inflammatory disease of the arteries. Early lesions (fatty streaks) contain monocytes and T lymphocytes which are recruited from the circulation by adhesion to activated vascular endothelial cells (EC). This process is described as the leukocyte adhesion cascade. Atherogenesis occurs predominantly at branches and bends of the arterial tree that are exposed to relatively low or re-circulating blood flow. Here we briefly review the effects of blood flow and shear stress on the leukocyte adhesion cascade and endothelial cell function.