This chapter opens with examples of the “new propaganda” permeating today’s public communications. It then explores shifting defi nitions of propaganda, noting contributions from diverse disciplines: political science, philosophy, social psychology, education, semantics, and communication theory. These defi nitions remind us that how we defi ne propaganda most assuredly determines whether we perceive the enterprise to be ethical or unethical. This section of the chapter is followed by a consideration of the social psychology and semantics of propaganda, given the signifi cance of belief systems and language behaviors in producing, consuming, and critically comprehending the phenomenon. Finally, the entire enterprise is redefi ned in a way that should inform further studies of this pervasive and oft-lamented component of modern society.