The Ninth International Workshop on Foundations of Models and Languages for Data and Objects (FoMLaDO) took place in Dagstuhl Germany, Sept- ber 18{21, 2000. The topic of this workshop was Database schema Evolution and Meta-Modeling; this FoMLaDO Workshop was hence assigned the acronym DEMM 2000. These post-proceedings contain the revised versions of the accepted papers of the DEMM 2000 workshop. Twelve regular papers were accepted for inclusion in the proceedings. The papers address the following issues: { Consistency of evolving concurrent information systems { Adaptive speci cations of technical information systems { Change propagation in schema evolution of object-based systems { Evolving software of a schema evolution system { Logical characterization of schema evolution { Con?ict management in integrated databases { Evolving relation schemas { Conceptual descriptions of adaptive information systems { OQL-extensions for metadata access { Metamodeling of schema evolution { Metricsfor conceptual schema evolution { Incremental datawarehouse construction In addition to the regular papers, there is an invited paper by Can Turk er on schema evolution in SQL99 and (object-)relational databases. Acknowledgements: We wish to thank the program committee members for their work on reviewing the submitted papers. We also wish to thank all a- hors for submitting papers to this workshop. Moreover, all participants of the workshop are thanked for contributing to lively discussions. Thanks also to Elke Rundensteiner, who delivered an invited talk on the SERF-project concerning ?exible database transformations.