Iron is an essential nutrient that is highly toxic in excess. Normal iron balance is maintained primarily by regulation of intestinal absorption of the metal from the diet. Iron overload generally results from a chronic increase in intestinal absorption. During the past 5 years, it has become apparent that there are at least eight inherited disorders of iron metabolism characterized by the toxic accumulation of iron. This review provides an update for pediatricians on the clinical features and pathogenesis of these disorders.