Over the last decade, the emergence of online social services has reshaped the landscape of our living world in many aspects, from social life, entertainment, to business, and politics. Social events, defined as online events happening on social websites, is of great importance in many applications, such as online personalized recommendation, behavioural targeting, computational advertising, public sentiment mining, personalized marketing, political campaign, cyber security, etc. Given the huge scale of available social data to be used, how to manage large-scale heterogeneous data of different types for scalable event identification and prediction has not been well addressed. When the number of discovered social events grows quickly, how to efficiently index large event databases for efficient event search, update, and relationship identification becomes evitable. Real-time event summarization and visualization also requires further research effort to quickly capture the essence of the events of users’ interests. The overall goal of the workshop is to bring people from different fields together, exchange research ideas and results, and encourage discussion on scalable social event processing and management.