William Gudykunst’s research focused on intercultural, interpersonal, and group communication across cultures and the development of intercultural competence. His early focus on consistent theory development made him one of the leading theorists in intercultural communication research. He was particularly interested in comparative cultural research between Japan and the United States. Gudykunst’s theory-driven, interdisciplinary, and applied research, which understands culture as a system of knowledge and competence, is guided by the conviction that intercultural misunderstandings can be reduced if interactants are conscious and mindful of their communication. This belief underlies his central theoretical model, the Anxiety/Uncertainty Management Theory (AUM Theory), according to which people need to reduce anxiety and uncertainty to communicate effectively across cultures. Thus, AUM theory was developed to promote understanding and improve communication.