Tim Muehlhoff (PhD, University of North Carolina at Chapel Hill) is a professor of communication at Biola University in La Mirada, California, where he teaches classes in family communication, interpersonal communication, persuasion, and gender. He is the author of and , and the coauthor of and . Muehlhoff and his wife, Noreen, are frequent speakers at FamilyLife Marriage Conferences, and he has served with Campus Crusade since 1986. They live in Brea, California, with their three boys.
Todd Lewis (Ph.D., Louisiana State) is professor of communication studies at Biola University, where he teaches courses in history and practice of oral interpretation and has coached intercollegiate forensics.