In an attempt to avoid methodological difficulties that have plagued past research on this issue, the present study used a proportional measure of corporal punishment, controlled for earlier behavior problems and other dimensions of parenting, and tested for interaction and curvilinear effects. Analyses were performed using a sample of Iowa families that displayed moderate use of corporal punishment and a Taiwanese sample that demonstrated more frequent and severe use of physical discipline, especially by fathers. For both samples, the level of parental warmth and control (support, monitoring, and inductive reasoning) was the strongest predictor of adolescent conduct problems. There was little evidence of a relationship between corporal punishment and conduct problems for the Iowa sample. For Taiwanese families, corporal punishment was not related to conduct problems when mothers were high on warmth and control, but was positively associated with conduct problems when mothers were low on warmth and control. An interaction between corporal punishment and warmth and control was found for Taiwanese fathers as well. For these fathers, there was also evidence of a curvilinear relationship, with the association between corporal punishment and conduct problems becoming much stronger at extreme levels of corporal punishment. Overall, results are consistent with the hypothesis that children feel angry and unjustly treated, defy parental authority, and engage in antisocial behavior when parents engage in severe forms of corporal punishment or administer physical discipline in the absence of warmth and involvement. 73 references, 7 tables, and 4 figures