From courtroom sentencing to graduate school admissions, from voting on the president to choosing who to sit next to on the bus, our biases play a role in the decisions we make and the actions we take. Most interventions designed to combat implicit bias do not hold up over time or simply do not reduce bias. Amidst these unsuccessful interventions, Mel Slater’s group at the University of Barcelona found one method that did reduce implicit bias of white people against black people and whose effects persisted for an unusually long time.