Iron deficiency and iron-deficiency anemia are common in the developing world. We evaluated the feasibility of iron fortification of domestic drinking water to prevent and control iron deficiency and iron-deficiency anemia. Twenty-one families representing 88 persons, including children, were selected to participate in this study. Twelve families added an iron solution plus ascorbic acid to their domestic drinking water over a four months period and nine families added a placebo. Blood samples were collected, before and after the four months, for hemoglobin and serum ferritin measurements. Iron-fortified drinking water increased hemoglobin (children 10.9 +/- 1.1 g/dl to 11.7 +/- 1.1 g/dl p < .01, adults 12.9 +/- 1.7 g/dl to 13.7 +/- 1.7 g/dl p < .01) and ferritin (children 27.6 +/- 21.6 ng/dl to 33.8 +/- 22.1 ng/dl, adults 74.8 +/- 41.3 ng/dl to 106.2 +/- 93.9 ng/dl p < .05). No significant changes in hemoglobin and ferritin were found in the placebo group after 4 months. Preparation, distribution, and consumption of the solutions were successful. Iron fortification of household drinking water can be a simple and effective alternative to deal with iron deficiency and iron-deficiency anemia in less developed areas.