To test the hypothesis that mothers with high self-concept will be more likely to breastfeed their infants than those with lower self-concept, 2 cohorts of mothers of term newborns were assessed by different forms of the Tennessee Self-Concept Scale. In study 1, mothers exclusively breastfeeding at 1 month postpartum had significantly higher self-concept than those exclusively formula feeding. In study 2, exclusively breastfeeding mothers had higher scores for total self-concept compared with those exclusively formula feeding. Exclusively breastfeeding mothers also scored higher on several individual dimensions of self-concept, notably those reflecting self-satisfaction, behavior, moral worth, value as a family member, and physical appearance. Mothers partially breastfeeding had intermediate levels of self-concept in both studies. Even after controlling for demographic and social factors and for breastfeeding initiation in regression analyses, self-concept remained significantly associated with exclusive breastfeeding in both studies. Thus, compared with mothers who exclusively formula feed their infants, exclusively breastfeeding mothers have higher levels of self concept.