Determinants of Schaefer's (1965) three dimensions of perceived parenting (Acceptance vs. Rejection, Psychological Control vs. Psychological Autonomy, and Firm vs. Lax Control) were investigated by administering a shortened Children's Reports of Parental Behavior Inventory to adolescent twins. The sample consisted of 46 pairs of identical twins and 43 pairs of fraternal twins residing with their natural parents. Analyses indicated that assumptions of the twin method were upheld and that neither sex main effects nor sex X zygosity interactions existed. The main analyses revealed that mothers' and fathers' use of Firm vs. Lax Control and Psychological Control vs. Psychological Autonomy was entirely determined by between family environmental factors. However, perception of Acceptance--Rejection showed evidence of genetic determination. (Author/MP)