Over the last thirty years, Castells has emerged as one of the world's leading communications theorists. In this, his most far-reaching book for a decade, he explores the nature of power itself, in the new communications environment. His vision encompasses business, media, neuroscience, technology, and, above all, politics. His case histories include global media deregulation, the misinformation that surrounded the invasion of Iraq, environmental movements, the role of the internet in the Obama presidential campaign, and media control in Russia and China. In the new network society of instant messaging, social networking, and blogging--"mass self-communication"--politics is fundamentally media politics. This fact is behind a worldwide crisis of political legitimacy that challenges the meaning of democracy in much of the world. Deeply researched, far-reaching in scope, and incisively argued, this is a book for anyone who wants to understand the dynamics and character of the modern world.