Book excerpt: This book constitutes the thoroughly refereed post-conference proceedings of the workshops held at the 11th International Conference on Web Engineering, ICWE 2011, in Paphos, Cyprus, in June 2011. The 42 revised full papers presented were carefully reviewed and selected from numerous submissions . The papers are organized in sections on the Third International Workshop on Lightweight Composition on the Web (ComposableWeb 2011); First International Workshop on Search, Exploration and Navigation of Web Data Sources (ExploreWeb 2011); Second International Workshop on Enterprise Crowdsourcing (EC 2011); Seventh Model-Driven Web Engineering Workshop (MDWE 2011); Second International Workshop on Quality in Web Engineering (QWE 2011); Second Workshop on the Web and Requirements Engineering (WeRE 2011); as well as the Doctoral Symposium2011, and the ICWE 2011 Tutorials.