Book excerpt: For more than twenty-five years, the authors have highlighted the complexities, subtleties, and pervasive influence of persuasive messages. The seventh edition again blends historical, rhetorical, and social psychological approaches to persuasion theory. The engaging discussions and multiple examples introduce the intricacies of social influence and highlight methods of presentation as well as evaluation. The dynamic topic of persuasion presents a constantly changing palette for analysis. The authors dissect theory and practice in multiple contexts—from interpersonal interactions to public communication and persuasive campaigns to advertising to politics. Twitter, YouTube, and social networking sites offer new media for persuasive appeals. The means of persuading one another changes constantly, yet much of what was written by Aristotle continues to be relevant. The production of persuasive messages and the study of message effects have been and will continue to be fertile ground for exploration. Persuasion is an interactive process requiring willing and attentive participants. Becoming responsible, ethical, and credible persuaders involves systematic thinking and informed preparation. The skills required for planning, composing, and delivering effective messages are equally useful for evaluating messages received. The seventh edition provides a thorough, up-to-date discussion of classic and contemporary theories of persuasion to aid readers in developing skills as effective persuaders and as critical consumers of persuasive messages.