This book constitutes the refereed proceedings of the 8th International Conference on Data Warehousing and Knowledge Discovery, DaWak 2007, held in Regensburg, Germany, September 2007. Coverage includes ETL processing, multidimensional design, OLAP and multidimensional model, cubes processing, data warehouse applications, frequent itemsets, ontology-based mining, clustering, association rules, miscellaneous applications, and classification.