Stephen G. Harkins received his Ph.D. at the University of Missouri-Columbia in 1975. Following a two-year postdoctoral fellowship at The Ohio State University, he moved to Northeastern University, where he has been a professor since 1989. He studies the effect of social threat on task performance. Kipling D. Williams received his Ph.D. at The Ohio State University in 1981. Since 2004, he has been a professor of psychological sciences at Purdue University. His primary research interests are ostracism and social influence. He is editor of the journal Social Influence. Jerry M. Burger received his Ph.D. at the University of Missouri-Columbia in 1980 and has been a professor of psychology at Santa Clara University since 1993. He has conducted extensive research in the areas of obedience, compliance, perception of and motivation for personal control, and social norms.