Societies transitioning from conflict and/or authoritarianism have increasingly built peace museums to explore their legacies of violence and repression, and to contribute to a culture of democracy, pluralism, and societal reconciliation. However, until recently, the impact of such museums had been assumed and not rigorously evaluated. In this talk, I will be presenting results of three different experimental studies I have conducted in peace museums/exhibits around the world: the Museum of Memory and Human Rights in Santiago, Chile (with Valeria Palanza and Elsa Voytas), the "Troubles and Beyond" exhibit in the Ulster Museum in Belfast, Northern Ireland (with Olwen Purdue and Elsa Voytas), and the United States Holocaust Memorial Museum in Washington, DC (with Francesca Parente and Ethan vanderWilden). I will offer comparative lessons from these three studies. In addition, I will present preliminary evidence from a transitional justice museum database we have recently built (with vanderWilden and Voytas) with the goal to examine macro-level patterns of post-conflict memorialistic initiatives around the world.