His research is focused on facilitating interdisciplinary research and teaching; knowledge organization has become the dominant element in that research agenda. He authored two books and several articles that develop classifications of things (phenomena), theories and methods applied, types of data, ethical perspectives, research practices, and relationships. He contributed to the Integrative Levels Classification and is developing the Basic Concepts Classification, and is collaborating on a book about interdisciplinary knowledge organization. He is exploring how these classificatory principles can be applied to galleries, museums, archives, and the Semantic Web, as well as to libraries.Rick Szostak. Classifying the Humanities. Knowledge Organization. 41(4), 263-275. 34 references.