Reflecting the ever-increasing changes in the public relations industry, this book offers a fresh, up-to-date look at public relations theories as well as theories from related areas that impact public relations. Chapters move from the oldest areas of communication theory through newer models devoted to interpersonal, organizational, and mediated, up to the most current theories devoted to emerging media, including digital and social. Readers will learn how public relations and persuasion theories are at the heart of a practitioner's day-to-day work, and see how a strong understanding of theories can make them more effective and strategic professionals.