Problems of indexing and index use lie at the heart of information use. They determine maximum possible use of information systems and sources, affect communication with users, influence the use of retrieved documents, and should form a more important field of research than past history indicates. Previous research provides some clues to user behavior and user needs; however, indexing systems are sometimes uncritically accepted as unproblematic for the user. Some work has tackled the user problem by trying to structure index systems from the user's own formulations of inquiries, but there is a strong feeling that more instruction is needed in schools to teach children how to make full use of indexes and index systems, to make better use of index skills in everyday life, and to view indexes as diverse ways of structuring knowledge and information. This paper presents examples of past research, a brief overview of current research methods, and suggestions for future research. A 34-item bibliography is attached. (Author/RAA)