E Commerce and Web Technologies : 11th International Conference EC Web 2010 Bilbao Spain September 1 3 2010. Proceedings This book constitutes the refereed proceedings of the 11th International Conference on Electronic Commerce and Web Technologies (EC Web) held in Bilbao Spain in September 2010. The 22 papers accepted for EC Web selected from 45 submissions are organized in topical sessions on recommender systems; e payment security and trust; service oriented e commerce and business processes; and agent based e commerce. The volume is completed by short summaries of the two invited talks on web advertising and electronic markets