Trace elements perform important functions in growth and development. However, little information exists about their dietary requirements during the demanding period of infancy. Opportunities to add to knowledge of the physiologic significance and dietary adequacy of trace elements in human nutrition are provided by recent analytic advances. Specific, sensitive, and reliable methods for the detection of trace element imbalances are sorely needed. Although several factors influence the dietary needs of these essential elements, the basis for establishing dietary needs in infants is hindered by the death of studies that have assessed their bioavailability in this age group. Thus until it has been conclusively shown otherwise, the physiologic response to human milk is used as the standard for infant feeding practices. This review is limited primarily to the physiologic significance and bioavailability of zinc, copper, manganese, molybdenum, chromium, fluoride, and selenium. The space devoted to each trace element is not meant to represent the element's importance but, rather, to reflect some of the present understanding of its metabolism and utilization.