The field of data mining comprises the design and analysis of efficient methods for the extraction of patterns from large data sets. Interest in this field has grown enormously over the past decade. The many scientific, industrial, and commercial applications of data mining include genomic analysis, intrusion detection, and personalization for electronic commerce. The first International Workshop on Rule-Based Data Mining, RBDM2001, held in conjunction with the 14th International Conference on Applications of Prolog (INAP2001), focused on data mining techniques, tools, and applications that employ a rule-based formalism as a primary component. Twelve papers from eight different countries were submitted to RBDM2001. Of these, six were accepted for inclusion in the conference proceedings. Three of these papers appear in the present collection and are briefy described below.