The purpose of this study was to examine the relationship between fathers' alcoholism and the quality of parent–infant interactions during free play. A related goal was to study the potential mediating or moderating role of comorbid parental psychopathology, such as depression and antisocial behavior, difficult infant temperament, and parental aggression. The sample consisted of 204 families with 12-month-old infants (104 alcoholic and 100 control families), recruited from New York State birth records. Results indicated that fathers' alcoholism was associated with a number of other risk factors (depression, antisocial behavior, and family aggression). Fathers' alcoholism was also associated with more negative father–infant interactions as indicated by lower paternal sensitivity, positive affect, verbalizations, higher negative affect, and lower infant responsiveness among alcoholic fathers. As expected, fathers' depression mediated the relationship between fathers' alcoholism and sensitivity, while maternal depression mediated the association between maternal alcohol problems and maternal sensitivity. Parents' psychopathology did not moderate the association between alcoholism and parent-infant interactions. The results from the present study suggest that the origins of risk for later maladjustment among children of alcoholic fathers are apparent as early as infancy and highlight the role of comorbid parental risk factors.