Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

This volume contains a collection of the papers presented during the First International ACM-L Workshop, which was held in Tucson, Arizona, on November 8, 2006, during the 25th International Conference on Conceptual Modeling, ER 2006. The workshop focused on enhancing the fundamental understanding of how to model continual learning from past experiences and how to capture knowledge from transitions between system states.

Active conceptual modeling is a continual process of describing all aspects of a domain, its activities, and changes from different perspectives based on our knowledge and understanding.

Included in this state-of-the-art survey are 11 revised full papers, carefully reviewed and selected from the workshop presentations. Rounded off with 4 invited lectures and an introductory and motivational overview, these papers represent the current thinking in conceptual modeling research.

This volume contains a collection of selected papers presented at the Symposium on Conceptual Modeling, which was held in Los Angeles, California, on December 2, th 1997, immediately before the 16 International Conference on Conceptual Modeling (ER'97), which was held at UCLA. A total of eighteen papers were selected for inclusion in this volume. These papers are written by experts in the conceptual modeling area and represent the most current thinking of these experts. This volume also contains the summaries of three workshops that were held on 6 7 December 1997, immediately after the ER'97 conference at UCLA. The topics of these three workshops are: * Behavioral Modeling * Conceptual Modeling in Multimedia Information Seeking * What Is the Role of Cognition in Conceptual Modeling? Since these topics are not only very important but also very timely, we think it is appropriate to include the summary of these three workshops in this volume. Those readers interested in further investigating topics related to the three workshops can either look up the individual paper published on the Web or contact the authors directly. The summary paper by Chen at the beginning of this volume also includes the summary of several interesting speeches at the Symposium.

The objective of the workshops associated with the ER'99 18th International Conference on Conceptual Modeling is to give participants access to high level presentations on specialized, hot, or emerging scientific topics. Three themes have been selected in this respect: - Evolution and Change in Data Management (ECDM'99) dealing with han dling the evolution of data and data structure, - Reverse Engineering in Information Systems (REIS'99) aimed at exploring the issues raised by legacy systems, - The World Wide Web and Conceptual Modehng (WWWCM'99) which ana lyzes the mutual contribution of WWW resources and techniques with con ceptual modeling. ER'99 has been organized so that there is no overlap between conference ses sions and the workshops. Therefore participants can follow both the conference and the workshop presentations they are interested in. I would like to thank the ER'99 program co-chairs, Jacky Akoka and Mokrane Bouzeghoub for having given me the opportunity to organize these workshops. I would also like to thank Stephen Liddle for his valuable help in managing the evaluation procedure for submitted papers and helping to prepare the workshop proceedings for publication. August 1999 Jacques Kouloumdjian Preface for ECDM'99 The first part of this volume contains the proceedings of the First International Workshop on Evolution and Change in Data Management, ECDM'99, which was held in conjunction with the 18th International Conference on Conceptual Modehng (ER'99) in Paris, France, November 15-18, 1999.