© 2019 by the Southern Political Science Association. All rights reserved. Research by Fortunato and Stevenson documents that, all else equal, voters infer that governing coalition partners share similar ideologies. All else may not be equal, however, if coalition partners counteract voters’ coalition-based heuristic by publicly emphasizing their policy differences. We argue that coalition partners are motivated to differentiate their policy images, and we review studies documenting these differentiation efforts via party press releases, interviews, speeches, and legislative amendments. We then report analyses of survey data from 21 European party systems that document that, the coalition heuristic notwithstanding, voters displayed only weak and inconsistent tendencies to perceive Left-Right policy convergence between coalition partners. However we argue for—and empirically substantiate—an alternative pattern, namely, that voters perceived coalition partners shifting their positions in the same direction over time, an effect that maintains stable perceived policy distances between parties. These findings have implications for parties’ election strategies and political representation.