this book constitutes the refereed proceedings of the 12th international conference on knowledge engineering and knowledge management, ekaw 2000, held in juan-les-pins, france in october 2000.the 28 revised full papers and six revised short papers presented were carefully reviewed and selected from a high number of high-quality submissions. the book offers topical sections on knowledge modeling languages and tools, ontologies, knowledge acquisition from texts, machine learning, knowledge management and electronic commerce, problem solving methods, knowledge representation, validation, evaluation and certification, and methodologies.