Dr. M. David Merrill is an instructional effectiveness consultant and emeritus professor at Utah State University. He has previously been a faculty member at George Peabody College, Brigham Young University-Provo, Stanford University, the University of Southern California, Utah State University, Brigham Young University-Hawaii, and Florida State University. Dr. Merrill has made major contributions to the field of instructional technology, including his development of the component display theory, elaboration theory, and instructional transaction theory. He has also published many books and articles in the field. He received his PhD from the University of Illinois.