This special issue of Canadian Social Studies, entitled Monumental Mistakes? Confronting Difficult Pasts, brings together a diverse range of scholars to explore the deeply contested nature of who and what from the past should be commemorated. These essays serve as accessible prompts for classroom and broader public conversations and inquiries into questions of who we are, wish to become, and in what ways we might better know ourselves through wrestling with difficult pasts and hoped for futures. Key words: History, history and social studies education, commemoration, public memory, politics of memory, reconciliations