In many parts of the world, deficiencies in vitamins, minerals and trace elements during the early months of life have dramatic consequences on the health and development of infants and young children. The nutritional status of the mother greatly influences breast-milk micronutrient levels and hence the nutritional status of the infant. This publication, written by leading investigators and clinicians, offers an up-to-date review of micronutrient requirements and the assessment of micronutrient status of mothers and young infants, followed by the epidemiology and health consequences of micronutrient deficiencies. It also includes different prophylactic and therapeutic approaches, such as the most recent research on both single and multiple micronutrient interventions during pregnancy, lactation and early infancy.