Curtis C. McKnight is emeritus professor of mathematics at the University of Oklahoma. He has his PhD from the University of Illinois. He served as national research coordinator and executive director of the U.S. National Center for the Second International Mathematics Study (SIMS). He served as the senior mathematics consultant to the U.S. Research Center for TIMSS. He is the author of more than 100 publications and papers. His specialties include cross-national comparative studies, cognitive studies of mathematics learning and performance, and curriculum policy studies such as those involved currently in U.S. calculus reform curricula. He has received more than 20 research grants and served as a consultant on many other projects.