David L. DuBois, Ph.D., is a Professor of Community Health Sciences in the School of Public Health at the University of Illinois at Chicago. He received his doctorate in clinical-community psychology from the University of Illinois at Urbana-Champaign. Dr. DuBois has conducted extensive research on youth mentoring with funding from a variety of sources, including the National Institutes of Health, Office of Juvenile Justice and Delinquency Prevention, and the Institute of Education Sciences. His most recent research includes a comprehensive update of his ground-breaking meta-analytic review of youth mentoring program effectiveness first published more than a decade ago. He is also co-author of After-School Centers and Youth Development: Case Studies of Success and Failure (Cambridge University Press, 2012). Dr. DuBois is a Fellow of the American Psychological Association and Society for Community Research and Action and a past Distinguished Fellow of the William T. Grant Foundation. He consults widely to mentoring programs nationally and internationally. Michael J. Karcher, Ed.D., Ph.D., is an Associate Professor of Education and Human Development at the University of Texas at San Antonio. He received a doctorate in Human Development and Psychology from Harvard University and a doctorate in Counseling Psychology from the University of Texas at Austin. He conducts research on school-based and cross-age peer mentoring as well as on adolescent connectedness and pair counseling. He currently conducts the Study of Mentoring in the Learning Environment (SMILE), which is a three-year research project funded by the William T. Grant Foundation to examine the effects of school-based mentoring.