This book explores the political economics and cultural politics of social media news sharing, investigating how it is changing journalism and the news media internationally. News sharing plays important economic and cultural roles in an attention economy, recommending the stories audiences find valuable, making them more visible, and promoting the digital platforms that are reshaping our media ecologies. But is news sharing a force for democracy, or a sign of journalism’s declining power to set news agendas? In Sharing News Online, Tim Dwyer and Fiona Martin analyse the growth of commendary culture and the business of social news, critique the rise of news analytics and dissect virality online. They reveal that surprisingly, we share political stories more highly than celebrity news, and they probe how deeply affect drives our sharing behaviour. In mapping the contours of a critical digital media phenomenon, this book makes essential reading for scholars, journalists and media executives.