This volume presents the proceedings of an international workshop on the processing of declarative knowledge. The workshop was organized and hosted by the German Research Center for Artificial Intelligence (DFKI) in cooperation with the Association for Logic Programming (ALP) and the Gesellschaft f}r Informatik (GI). Knowledge is often represented using definite clauses, rules, constraints, functions, conceptual graphs, and related formalisms. The workshop addressed such high-level representations and their efficient implementation required for declarative knowledge bases. Many of the papers treat representation methods, mainly concept languages, and many treat implementation methods, such as transformation techniques and WAM-like abstract machines. Several papers describe implemented knowledge-processing systems. The competition between procedural and declarative paradigms was discussed in a panel session, and position statements of the panelists are included in the volume.