This book constitutes the refereed proceedings of the 23rd International Conference on Conceptual Modeling, ER 2004, held in Shanghai, China, in November 2004.

On behalf of the Organizing Committee, we would like to welcome you to the proccedings of the 23rd International Conference on Conceptual Modeling (ER 2004). Th

This volume constitutes the refereed proceedings of the 17th International Conference on Conceptual Modeling, ER '98, held in Singapore, in November 1998. The 3