In a sample of low-income families (N = 239), structural equation models assessed predictors of fathers' involvement with preschool-aged children in instrumental, behavioral, and emotional realms. Results suggest that parental conflict has a strong negative relation with father involvement. Fathers' human capital characteristics, healthy psychosocial functioning, and past stability in family relationships all predicted greater father involvement directly and/or indirectly through parental conflict. Numerous differences emerged in the predictive models between resident and nonresident fathers, although few differences were statistically significant. Results suggest that policy efforts aimed at enhancing fathers' responsible parenting should focus both on increasing fathers' human and social capital and on supporting positive family processes.