th This volume contains the papers presented at the 13 International Conference on Knowledge Engineering and Knowledge Management (EKAW 2002) held in Sig enza, Spain, October 1-4, 2002. Papers were invited on topics related to Knowledge Acquisition, Knowledge Management, Ontologies, and the Semantic Web. A total of 110 papers were submitted. Each submission was evaluated by at least two reviewers. The selection process has resulted in the acceptance of 20 long and 14 short papers for publication and presentation at the conference; an acceptance rate of about 30%. In addition, one invited paper by a keynote speaker is included. This volume contains 8 papers on Knowledge Acquisition, 4 about Knowledge Management, 16 on Ontologies, and 6 papers about the Semantic Web. This was the second time (EKAW 2000 being the first) that the event was organized as a conference rather than as the usual workshop (hence the acronym: European Knowledge Acquisition Workshop). The large number of submissions (110 versus the usual 40-60) is an indication that the scientific community values EKAW as an important event to share experiences in the Knowledge Technology area, worthy of being organized as a prestigious international conference. Knowledge is the fuel of the upcoming Knowledge Economy. Therefore, we believe that conferences such as EKAW, that focus on Knowledge Technologies, will continue to play a major role as a platform for sharing and exchanging experiences and knowledge between key players in the area.