Illegal online file sharing costs companies tens of billions of dollars of lost revenues around the world annually and results in lost productivity, various psychological issues, and significant reduction of incentives to create and innovate. Legislative, technical, and enforcement efforts have failed. This book presents psychological theories about why people illegally share files online; analyzes and characterizes optimal sanctions for illegal online file sharing; introduces new models for pricing of network-access and digital-content to help reduce illegal online file sharing; introduces new content control and P2P systems; and explains why game theory does not work in pricing of network access.