Many contemporary injustices have their roots in histories of slavery, colonialism, and post-slavery racism. Decolonial movements seek to redress the harmful legacies of these injustices, for instance by challenging individual, institutional and structural forms of racism. One example of a decolonial movement is the Countering Colston campaign in Bristol, which has sought to change how Bristol memorializes the history and legacies of its role in slavery. Countering Colston has challenged uncritical memorials of those who built the institutions of slavery, and has campaigned for a major memorial honouring the lives of the enslaved. On the surface of it, this kind of campaign may seem to be at odds with the principles of Effective Altruism; symbolic repair for historical injustice may seem like a poor use of energy. I argue that this impression is mistaken. Finding the most responsible and constructive ways to address legacies of historical injustices of slavery and colonialism is important, and has potentially far-reaching benefits for communities across the globe. I defend this claim by reference to the EA criteria, which encourage us to direct attention towards problems that are 1) great in scale, 2) highly neglected, and 3) highly solvable. Finding the best forms of symbolic, expressive repair has the potential to substantially improve both psychological and physical wellbeing of groups who have suffered injustice; many solutions are replicable at scale globally; symbolic actions can be meaningful to large numbers of people; and these campaigns often motivate people to address other forms of injustice. However, acts of symbolic repair are also risky, with potential to increase polarization, generate political unrest and lead to retrenched racist attitudes. The complexity of these issues, along with their global relevance, makes them an important area for further research. In defending these claims, I highlight key principles for Decolonial Activists and Effective Altruists to learn from one another. Learning these principles will help both movements have a more positive global impact.