The present recommended dietary interpretation of the effects of both maternal nutritional status and diet on the yield and composition of milk is complicated by disparities between the methods of sampling, collection of samples and analysis in these studies. The effect of breast-feeding on the growth of the neonate and the desirable period during which unsupplemented breast-feeding can be safely given are discussed. Well coordinated studies worldwide on the effect of lactation on maternal and infant health and on the nutrient requirements of infants are urgently needed in view of recent developments regarding the true protein value of breast milk. The let-down reflex must be considered. Three main strategies, including supplementary feeding of the mother, for improving breast-feeding potential among mothers who want to suckle their infants are outlined.