Hyperlipidemia in children has emerged as an increasingly prevalent risk factor in children, concomitant with the worldwide epidemic of obesity. Hyperlipidemia can alter vascular endothelial function and impair some of its pro-fibrinolytic and anti-thrombotic regulatory properties, as well as initiate the atherosclerotic process. There are strong links between vascular changes and hyperlipidemia in children, both from pathologic and non-invasive assessment studies. More severe lipid abnormalities in children are related to primary familial dyslipidemias. Current recommendations for screening begin with assessment of family history for cardiovascular disease or events or parental hyperlipidemia. High-risk individuals merit more intensive investigation and intervention. While fat-restricted diets have been shown to be safe in children, lipid-lowering is modest. Those with more severe lipid abnormalities may meet criteria for drug therapy, and the statin agents commonly used in adults are increasingly being used in high-risk children, with similar efficacy and safety, although long-term concerns remain.