Across the globe, education is essential to social mobility, bettering the lives of individuals and moving whole nations from poverty to affluence. Yet educational opportunity and the upward mobility it can bring are not equally available to everyone. In rich and poor nations alike, the disadvantaged--defined by gender and geography, race and religion, class and caste--fall behind, losing the chance to improve their lives and depriving society of the contributions they might have made. Even in countries where access to education is expanding rapidly, these gaps persist, as social stratification perpetuates itself across generations and schooling too often fails to make up for family disadvantage. Because every culture is different, the contours of the problem vary from place to place; what counts as failure in one country may look enviable somewhere else. Everywhere, however, eliminating educational and social-mobility gaps is a complicated endeavor that demands concerted effort from politicians and bureaucrats, teachers and university administrators, employers and policy advocates. Although economic growth is a prerequisite of gap-closing, growth alone cannot accomplish the task. It takes an effort of will to enact and implement the policies that can make a difference: training effective teachers, extending schooling to the youngest children, ensuring that all students complete their educations and coordinating university training with the demands of the labor market. With a host of compelling issues crowding the international agenda, advocates need to deploy new kinds of arguments as they strive to convince funders and policymakers of the urgency of this work. The complex intertwining of educational opportunity and social mobility was the focus of "Optimizing Talent: Closing Educational and Social Mobility Gaps Worldwide," a conference co-sponsored by the Educational Testing Service (ETS) and the Salzburg Global Seminar (SGS) and supported by the Lumina Foundation for Education. The conference, held October 3-7, 2010, in Salzburg, Austria, brought together 34 researchers, policy advocates and university administrators from around the world and set them to work defining the issues that will structure two future ETS/SGS conferences on global education issues. This issue of "ETS Policy Notes" provides an overview of the conference. (Contains 2 figures and 2 tables.)