 Zinc is necessary for growth and development, including the central nervous system, and zinc deficiency which is common in resource-poor settings, may adversely affect social, behavorial, cognitive and sensorimotor development. The project, located in Lima Peru, utilizes an experimental model in which children receive 10 mg supplemental zinc or not daily along with 10 mg iron and 12 mg copper from 6 months of age to 18 months of age. Beginning at 6 months of age, and at 9, 12, and 18 months, children are evaluated in multiples aspects of development. Children are also followed for their diet, growth, and health status. We hypothesize that children in this setting in which the diet is low in zinc who receive supplemental zinc will have better information processing skills, sensorimotor and behavioral development than their counterparts who do not receive supplemental zinc. 