Scavenger receptors bind and internalize modified low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Because the expression of scavenger receptors is not down-regulated by cholesterol, macrophages (M) expressing scavenger receptors can internalize substantial quantities of cholesteryl ester from oxidized LDL and HDL, leading to foam cell formation. M express several different classes of the growing scavenger receptor family on their cell surface and their relative contribution to M cholesterol physiology and atherogenesis is the subject of intense investigation. We focus on the potential role of two scavenger receptors, macrosialin and SR-BI/II in M cholesterol metabolism. Macrosialin is a predominantly M-specific oxidized LDL-binding protein and an atherogenic diet markedly up-regulates its hepatic expression in atherosclerosis-susceptible and atherosclerosis-resistant mouse strains. The HDL receptor, SR-BI and its splicing variant SR-BII, colocalize with caveolin in caveolae in M. Caveolae are initial acceptor sites for cholesteryl esters and these findings indicate a possible role for caveolae and SR-BI in M-selective lipid uptake and in regulating M cholesterol flux in the vascular wall. J. Leukoc. Biol. 66: 740–746; 1999.