This study examined amount and type of mother-adolescent conflict and joint decision making in predicting a syndrome of adolescent problem behavior. Subjects, 73 adolescents ages 14 to 18 and their mothers, completed measures of conflict and decision making related to everyday household routines, adolescent deviant behavior, and adolescent behavior toward others. In addition, adolescents reported their engagement in delinquency, unprotected sexual activity, and substance use. Results indicated that higher levels of conflict over adolescent deviant behavior were associated with higher levels of problem behavior, and there was evidence to suggest that conflict over everyday household routines was associated with lower levels of problem behavior. Increased proportions of joint decision making were also associated with less problematic behavior, although only slightly. Results are consistent with a model in which effective management of family conflict, including joint decision making, may play an important role in promoting adolescent autonomy and limiting the extent to which young people engage in problematic behavior. (BB)