Clark Callahan received his Ph.D. in communication from the University of Oklahoma (2002), an M.A. from West Texas A&M (1995), and a B.A. in communications from BYU (1995). He teaches courses in intercultural and international communication, theory, and research methods. He formerly taught at Penn State York and the University of South Dakota. His research centers on theories of intercultural adaptation, historical diffusion of innovations, and media ecology. He has served as editor for Comparative Cultures and Civilizations for Hampton Press and is an editorial board member for several other communication journals.
As a specialist in communication leadership and organizational communication, he has consulted for the United States Department of Defense, the Internal Revenue Service, the state of South Dakota, and multiple regional and local governmental organizations. He has received top research awards through the National Communication Association and the International Communication Association. He has been recognized for teaching distinction by the International Communication Association, the University of Oklahoma, and the University of South Dakota.