Information we receive from and create together with our social networks is becoming increasingly important. Social information has in many ways a great impact on our information behaviour and there are many possible angles and layers in studying social aspects in information science. This book presents some of these angles. This book is relevant for various actors in the library and information science field and will be useful for researchers, educators and practitioners while coordinating empirical research on social information and by providing an overview of some of the present research about social information.