This book constitutes the refereed proceedings of the 4th Pacific-Asia Conference on Knowledge Discovery and Data Mining, PAKDD 2000, held in Kyoto, Japan, in April 2000. The 33 revised full papers and 16 short papers presented were carefully reviewed and selected from a total of 116 submissions. The papers are organized in sections on data mining theory; feature selection and transformation; clustering; applications of data mining; association rules and related topics; induction; text, web, and graph mining.