The effects of infant behavior on the transition to parenthood were examined. The primary interest was the relationship between the amount of obligatory infant behavior (behavior that required action on the part of the parents) and the parents' perceptions both of their transition to parenthood and of their infant in terms of an “average” baby. The concepts of normative change, parental perceptions of role competence, and parental self-esteem were examined as intervening variables.Data were collected in the last trimester of pregnancy and at one month after delivery. Findings indicated that the amount of obligatory infant behavior does have an effect on the ease of transition to parenthood and on both parents' perceptions of the infant. The relationships in the research model were found to be better supported for mothers than for fathers, but most of the predicted relationships were supported for both. Fathers experienced less normative change than mothers, and made an easier transition. Mothers, on the other hand, reported higher self-perceptions of role competence.