17 β-estradiol (E 2) protects against atherosclerosis independent of changes in plasma lipoproteins in a variety of animal models, which is explained by direct effects of E 2 on the vascular wall. E 2 improves vasomotion by modulation of vasoconstrictor and vasodilator systems through endothelium-dependent and endothelium-independent mechanisms. E 2 affects the remodeling of the vascular wall by inhibiting smooth muscle cell proliferation and accelerating reendothelialization of injured blood vessels. E 2 modulates the vascular inflammatory response by inhibiting cytokine production, cyto-kine-induced expression of cell adhesion molecules and platelet aggregation/adhesion. This review focuses on the cellular and molecular mechanisms underlying these vasculoprotective actions of E 2.