Predictors of paternal participation in childcare and housework are examined. A longitudinal sample of 66 couples expecting their 1st child completed extensive questionnaires during the wives' last trimester of pregnancy and 3–8 months after birth. Regressions were conducted in which paternal participation in childcare and housework were regressed on variables pertaining to each of 4 models of paternal participation: relative economic resource, structural, family systems, and sex role attitude. Composite models of paternal participation in housework and childcare were then developed. Fathers' involvement in childcare is best explained by mothers' work hours and fathers' feminism. Fathers' contribution to housework seems best explained by discrepancies in income between spouses, wives' occupational prestige, and dynamics in the marriage. Differences in the determinants of fathers' contributions to childcare and housework are discussed.