SIG/CR studies the fundamental principles, underlying processes, and analytic constructs of classification schemes and procedures by humans or automata. It is concerned with organizing information, and includes indexing, index construction, indexing language, thesaurus construction, terminology, classification of information in any form, and testing and evaluating the effectiveness of these products. It is also concerned with the ability to develop abstractions from perceived reality. Theoretical emphases include cognition, grouping and organization of groupings, and linguistics.

Dr. Exner teaches a wide range of courses, both on campus and via distance education.