Johnny Blair is an independent consultant. Previously, he was a principal scientist and senior survey methodologist at Abt Associates Inc., where he directed the Cognitive Testing Laboratory. He has conducted research on sampling rare populations, measurement error in proxy reporting, and cognitive interviewing for pretesting survey instruments. He has been a member of the Design and Analysis Committee, which provides statistical advice for the National Assessment of Educational Progress (NAEP), often referred to as The Nation’s Report Card. He has served on National Research Council panels to assess major government-sponsored surveys. His research publications include many book chapters and over 50 articles in academic journals and in the Proceedings of the Joint Statistical Meetings of the American Statistical Association Section on Survey Methods. He served two terms on the editorial board of Public Opinion Quarterly and is a frequent peer reviewer for several other research journals.   Ronald Czaja, associate professor (retired) of sociology and anthropology at North Carolina State University, taught courses in both undergraduate and graduate research methodology and medical sociology. His methodological research interests focus on sampling rare populations, response effects in surveys, and the cognitive aspects of questionnaire design. From 1969 to 1990 he was at the Survey Research Laboratory, University of Illinois at Chicago, as project coordinator, co-head of sampling, assistant director, and principal investigator. Edward Blair is the Michael J. Cemo professor of marketing and entrepreneurship and chair of the Department of Marketing and Entrepreneurship in the Bauer College of Business at the University of Houston. He has been chair of the American Statistical Association Committee on Energy Statistics, which advises the U.S. Energy Information Administration on statistical matters, and previously served on the U.S. Census Bureau Advisory Committee. He has been a National Science Foundation panelist, national conference chair for the American Marketing Association, editorial board member for Journal of Marketing Research, Journal of the Academy of Marketing Science, and Journal of Business Research, and instructor in sampling and survey methods for the American Marketing Association School of Marketing Research. His research interests include survey sampling and cognitive aspects of survey methodology.