Many goals involve and require the cooperation of others, such as co-workers, family members and friends. But joint endeavors are often sabotaged by misunderstandings (and sometimes by bad behavior). To succeed with joint action, you need something rarely understood today: objectivity—objectivity both about yourself and about the other person. This talk explains how to be objective about each individual’s knowledge, values and actions, and how such objectivity gives your joint effort its best chance for success, even if your partner is not a hero of rationality.