This book examines how Fortune 500 companies use Twitter on a daily basis. Chapters include an introduction explaining the importance of Twitter to companies by discussing some of the most damaging 140-character reputational mishaps and some impressive crisis management strategies executed within the Twittersphere. A comprehensive review is presented beginning with a discussion of computer-mediated communication (CMC), interactivity, word-of-mouth (WOM), message valence, and ending with a section differentiating between business-to-consumer (B2C) and business-to-business (B2B) companies. Lastly, the methodology, operationalizations, and research design are presented to examine companies¿ interactivity with users, message valence, how B2Bs differ from B2Cs, and how long users can expect to wait for a company to respond to their tweet.