Charles Teddlie (Ph.D., Social Psychology, University of North Carolina at Chapel Hill) is the Jo Ellen Levy Yates Distinguished Professor of Education at Louisiana State University (LSU). He has also taught at the University of New Orleans and has been a Visiting Professor at the University of Newcastle-upon-Tyne (U.K.). He has also served as Assistant Superintendent for Research and Development at the Louisiana Department of Education. His major writing interests are social science research methodology and school effectiveness research. Professor Teddlie has taught research methods courses for over twenty years, including statistics and qualitative research methods. He has been awarded the Excellence in Teaching Award from the LSU College of Education. Professor Teddlie has lectured on school effectiveness research and educational research methodology in several countries including the United Kingdom, the Republic of Ireland, the Netherlands, Norway, Denmark, Russia, the Ukraine, and Belarus. Abbas Tashakkori (Ph.D., Social Psychology, University of North Carolina -Chapel Hill) is the Chairperson of the Department of Educational Psychology at the University of North Texas (Denton, Texas, USA). Previously, has has been a Professor of Research and Evaluation Methodology at Florida International University (Miami, Florida, USA). He has been a post-doctoral fellow at the Carolina Population Center and the University of North Carolina at Chapel Hill, as well as a visiting scholar at Texas A&M University. He has extensive experience as a program evaluator, and he has taught research methods for more than two decades in undergraduate and graduate programs at the University of North Carolina, Shiraz University, Stetson University, Louisiana State University, and Florida International University. In addition to research methodology, his published work covers a wide spectrum of research and program evaluation in cross-cultural and multi-cultural contexts, including self-perceptions, attitudes, and gender/ethnicity.