This volume focuses on the responsibilities of online service providers (OSPs) in contemporary societies. It examines the complexity and global dimensions of the rapidly evolving and serious challenges posed by the exponential development of Internet services and resources. It looks at the major actors - such as Facebook, Google, Twitter, and Yahoo! - and their significant influence on the informational environment and users' interactions within it, as well as the responsibilities and liabilities such influence entails. It discusses the position of OSPs as information gatekeepers and how they have gone from offering connecting and information-sharing services to paying members to providing open, free infrastructure and applications that facilitate digital expression and the communication of information. The book seeks consensus on the principles that should shape OSPs' responsibilities and practices, taking into account business ethics and policies. Finally, it discusses the rights of users and international regulations that are in place or currently lacking.