This book constitutes the refereed proceedings of the 12th International Conference on Advanced Information Systems Engineering, CAiSE 2000, held in Stockholm, Sweden, in June 2000. The 32 revised full papers presented together with an invited contribution and statements of a panel discussion were carefully reviewed and selected from 126 submissions. The papers are organized in topical sections on Web-based information systems and services, workflow models and systems, patterns and components, enterprise application integration, the information systems development process, reuse, reengineering, modeling language, databases and data warehousing, and industrial processes.