The authors bring psychological research to bear on an examination of the policy of affirmative action. They argue that data from many studies reveal that affirmative action as a policy has more benefits than costs. Although the majority of pro-affirmative action arguments in the social sciences stress diversity, the authors' argument focuses on issues of merit. The merit-based argument, grounded in empirical studies, concludes that the policy of affirmative action conforms to the American ideal of fairness and is a necessary policy.