Structural inequalities between members of more advantaged and more disadvantaged population groups are a central feature of all societies. These inequalities are deeply rooted in the past and have been carried forward into the present. Their persistence severely undermines local, national, and global efforts to promote advances in the quality of life and well-being of people at all levels of social, political, and economic organization. They also are among the root causes of many of the civil wars and recurrent intraregional conflicts that interfere with national and international social progress.