In the United States, coronary heart disease is the major cause of death and disability in women and in men. Despite this, little is known about the risk factors, including cholesterol and lipoprotein concentrations, for coronary disease in women. In this paper we review the determinants of cholesterol and lipoprotein concentrations in women, assess whether values for total cholesterol and lipoproteins (HDL and LDL) are associated with the occurrence of coronary heart disease in women, and evaluate the evidence that suggests that modifying the concentrations of lipids in women is associated with changing the risk of coronary disease. Besides genetic determinants, dietary cholesterol, dietary fat, total caloric intake, alcohol consumption, cigarette smoking, and physical activity are known to influence concentrations of lipids in women. Some of the strongest determinants of cholesterol and lipoprotein concentrations in women are sex hormones, including estrogen and progestin. Exogenous use of both of these hormones markedly influences HDL and LDL cholesterol; additional evidence suggests that endogenous sex hormones also influence lipid and lipoprotein concentrations. The few studies that have examined the association of total cholesterol with coronary heart disease occurrence and mortality in women have consistently shown that (a) women have much lower rates of coronary heart disease than men at the same values for cholesterol, and (b) clearly elevated risk for coronary heart disease in women is evident only at relatively high values of total cholesterol (i.e., greater than 260 mg/dL). There also appears to be an age effect, with total cholesterol concentrations being more predictive in older than in younger women.