This paper proposes an customization technique to supporting interactive document retrieval in unorganized open information space like WWW. We assume that taxonomical thought is one of the most important and skilled operations for us when we organize or store information. The proposed methodology, therefore, handles hierarchical categories of documents. The system can be customized through users’ modification of categories. The features of the proposed approach are (1) visualization of document categories for interaction, (2) initialization of categories by hierarchical clustering method, (3) customization of categories by support vector machine techniques, (4) additional attributes for individual implicit cognitive aspects.