In an ideal world, social science research would provide a strong basis for advocacy and social policy. However, advocates sometimes misunderstand or even ignore scientific research in pursuit of their goals, especially when research pertains to controversial questions of social inequality. To illustrate the chasm that can develop between research findings and advocates’ claims, this article addresses two areas: (a) the effects of the gender diversity of corporate boards of directors on firms’ financial performance and (b) the effects of the gender and racial diversity of workgroups on group performance. Despite advocates’ insistence that women on boards enhance corporate performance and that diversity of task groups enhances their performance, research findings are mixed, and repeated meta-analyses have yielded average correlational findings that are null or extremely small. Therefore, social scientists should (a) conduct research to identify the conditions under which the effects of diversity are positive or negative and (b) foster understanding of the social justice gains that can follow from diversity. Unfortunately, promulgation of false generalizations about empirical findings can impede progress in both of these directions. Rather than ignoring or furthering distortions of scientific knowledge to fit advocacy goals, scientists should serve as honest brokers who communicate consensus scientific findings to advocates and policy makers in an effort to encourage exploration of evidence-based policy options.