A national, longitudinal data collection regarding contemporary WIC infant and toddler feeding practices, including the duration of breastfeeding, the age and pattern of introduction of foods other than breast milk or formula, and the age of introduction of cow’s milk. The study is examining the influences that shape a mother’s infant and toddler feeding decisions and describing the changes in feeding practices as the children develop. This study also collects information on nutrition education, breastfeeding promotion, and support provided to participants.