The first aim of this study was to examine the factors that might account for variations in the level of parent-adolescent conflict. These factors were grouped into two classes of variables: (1) personal characteristics of the adolescent, such as temperament and pubertal timing; and (2) parental childrearing style. Second, we examined the relationship between the level of conflict, the quality of the parent-adolescent relationship, and adolescents' and parents' well-being. The sample consisted of 508 families with adolescents (12 to 18 years old). During a home visit, a battery of questionnaires was administered individually to mothers, fathers, and adolescents. The amount of conflict was related to the temperamental characteristics of the adolescent but not to pubertal timing or child-rearing style. With regard to the consequences of the parent-adolescent conflict, it appears that a higher level of conflict is a better predictor of parental, rather than adolescents' well-being.