Many organizations use tools like RACI to clarify who should provide input on decisions, who should make them, and who should carry them out. But in practice these frameworks often fail because teams don’t apply them properly. Drawing on their research and their work with more than 100 companies, the authors identify four common mistakes: setting decision roles before clarifying goals, treating decision rights as a static list created by a single senior leader, misunderstanding what each role actually means, and letting hierarchy override the assigned roles. To avoid these issues, leaders should cocreate roles with the people involved in or affected by the decisions, define clear behaviors for each role, revisit role assignments regularly, and have ongoing conversations about them. Used well, tools like RACI will reduce conflict, improve collaboration, and increase the quality of decisions and the speed at which they’re made.