Privacy coordination between adolescents and their parents is difficult, as adolescents' changing roles require adjustments to expectations about family boundaries. Adolescents' perceptions of privacy invasion likely provoke conflicts with parents, but higher levels of conflict may also foster invasion perceptions. This longitudinal study assessed relations between privacy invasion and conflict frequency among adolescents, mothers, and fathers (N = 309). Bidirectional relations were present; all reports showed that invasion provoked conflict in later adolescence, but the timing and direction of conflict-to-invasion relations differed between respondents and measurement waves. The findings suggest a functional role for conflict in adolescent-parent privacy negotiations, in that it both draws attention to discrepant expectations and provides youths with a means of directly managing perceived boundary violations.