Two alternative theoretical models of parenting, identity theory and parental investment theory, are investigated as sources of explanation of men's fathering attitudes and behaviors. Four dimensions of fathering are explored: responsivity, harshness, behavioral engagement, and affective involvement. Concepts from identity theory operationalized as predictors include father role salience, role satisfaction, and reflected appraisals. From parental investment theory, concepts included investment maximization, contingent commitment, and paternity certitude. Using telephone survey data drawn from a community-based probability sample of 208 fathers, each of the four individual indicators of fathering and a composite fathering measure were regressed against the theoretical predictors in hierarchical regression analyses. Both theoretical models were significant, with identity theory predictors accounting for a greater proportion of variance than the parental investment theory predictors. This study underlines the importance of social psychological variables to understanding variations in men's commitments to children.