Although many fathers today spend more time with children than was the case in the past, physical care of young children remains primarily mothers' work. Yet some fathers claim that they do work traditionally seen as the "mother's job" every day. Using subsample data from the male respondent file of the National Survey of Family Growth 2002 (n = 613), this study examines factors associated with married or cohabiting fathers' daily involvement in physical care of children under age 5 years. Logistic regression results show that daily involvement is more likely if fathers were raised by their biological fathers, received more education, have employed wives or partners, have a young male child, or receive public assistance; it is less likely if they have school-age children. This study suggests that paternal involvement in physical care of young children is shaped by multiple factors including childhood experiences, education, economic conditions, and current family context. (Contains 4 tables.)