This paper highlights the rationale for exclusive territories in a model of repeated interaction between competing supply chains. We show that with observable contracts exclusive territories have two countervailing effects on manufacturers’ incentives to sustain tacit collusion. First, granting local monopolies to retailers softens competition in a one-shot game. Hence, punishment profits are larger, thereby rendering deviation more profitable. Second, exclusive territories stifle deviation profits because retailers of competing brands adjust their prices to the wholesale contract offered by a deviant manufacturer, whereas intrabrand competition prevents such “instantaneous reaction.” We show that the latter effect tends to dominate, ...