This book constitutes the refereed proceedings of the 19th International Conference on Web Engineering, ICWE 2019, held in Daejeon, South Korea, in June 2019. The 26 full research papers and 9 short papers presented were carefully reviewed and selected from 106 submissions. Additionally, two demonstrations, four posters, and four contributions to the PhD symposium as well as five tutorials are included in this volume. The papers cover research areas such as Web mining and knowledge extraction, Web big data and Web data analytics, social Web applications and crowdsourcing, Web user interfaces, Web security and privacy, Web programming, Web services and computing, Semantic Web and linked open data applications, and Web application modeling and engineering.

This book constitutes the thoroughly refereed post-workshop proceedings of the 21th International Conference on Web Engineering, ICWE 2021, held in Biarritz, France, in May 2021.* The first international workshop on Big data-driven Edge Cloud Services (BECS 2021) was held to provide a venue in which scholars and practitioners can share their experiences and present on-going work on providing value-added Web services for users by utilizing big data in edge cloud environments. The 5 revised full papers and 1 revised short contribution selected from 11 submissions are presented with 2 invited papers. *The conference was held virtually due to the COVID-19 pandemic.