Transition to parenthood has long been examined from the angle of mothers' experience. When looked at this transition through fathers' lens, fathers' involvement and perceived parental efficacy appear to be landmarks of this experience. This article examines a model of the relationships among father involvement, perceived parental efficacy, events related to breastfeeding, support, stress, and income with a sample of 164 fathers of breastfed infants. This model highlights the direct and indirect contributions of support and stress to fathers' perceived parenting efficacy and involvement. Possible directions for nursing practice, education, and research are proposed to ease men's transition to fatherhood.