This paper addresses the impact of both external democratic and authoritarian actors on the quality and stability of non-democratic regimes in third countries. We ask how interdependences contribute to regime stability. We advance the literature on the role of diplomatic ties, trade and migration linkages by providing comparative evidence on the underlying mechanisms supporting stability in its political and economic dimensions. We argue that the dominant mechanisms which translate international linkages into regime stability vary with the type of interdependence. We draw on evidence from three comparative case studies of post-Soviet states and their interdependences with Russia and the EU.