What difference does the amount of decision-making power exercised by teachers in schools make for how well schools function? This article reports on a study that used national data to examine the effects of two kinds of decision-making power that teachers wield in regard to core educational issues in high schools-the faculty's collective influence over school policy and the autonomy of individual teachers in the class- room-on the degree of conflict among teachers, students, and adminis- trators. The results indicate that increases in both faculty influence and teachers' autonomy are significantly associated with decreases in school conflict, but that the strength of the relationship depends on the issues that are controlled. In particular, the results draw attention to the importance of teachers' power over activities concerned with the crucial, but often overlooked, sorting and socialization functions in schools