Communication scholarship has profited greatly by the rise of social science during the mid-20th century. This scientific progress has been marked by increased outlets for peer-reviewed research, thriving sub-disciplines, and a rapidly accumulating corpus of findings. Social scientists have accomplished this feat largely by conducting tests of empirical models and their associated constructs. Over the same span of time, the discipline’s most prolific researcher, James C. McCroskey, pioneered the study of the construct with which he is most closely associated. Communication apprehension (CA) has impelled generations of scholars to investigate possibly the greatest impediment to successful communication, namely the fear of interacting with fellow humans. Tracing its development reveals that CA meets the standards for theory bridges: truth, abstraction, progress, and applicability. Consequently, describing CA as a bridge construct rests on four interrelated claims. First, the primary aim of CA research is to discover the truth about social anxiety. Studies of CA have outstripped competitor explanations for speaker anxiety by yielding an extensive literature of peer-reviewed articles, books, and doctoral dissertations. These writings are predicated on the presumption that CA taps into the true nature of social anxiety. Second, self-reported measures of CA, such as the PRCA-24, allow for enough abstraction to support scientific generalization. This makes it possible for CA researchers to connect concrete observations to abstract principles. Third, CA research contributes to scientific progress in communication. Explanations for CA have generally reflected theories and perspectives at the horizon of the field. Last, CA research impacts on the quality of everyday life. Ultimately, CA researchers seek to develop treatment and educational strategies for the one-fifth of the general population afflicted with this condition. Taken together, CA has served as a bridge construct that enables scholars to pursue truth, formulate testable generalizations, achieve scientific progress, and potentially improve the quality of human life.