Swift et al. (1978) discuss the limitations of an aboutness approach to indexing in the social sciences. They recommend indexing documents according to the “problems” to which they seem to relate. It is difficult to see how the distinction they make differs from the distinction, made earlier in this chapter, between what an item deals with and why a particular user or group of users might be interested in it. Crowe (1986) maintains that the indexer should address the “subjective viewpoint” of the author. One of her examples deals with the topic of depression which can be discussed in books or articles from several different viewpoints (e.g., treatment through psychotherapy, through drug therapy, and so on). Again, it is difficult to see how this differs form normal indexing practice as exemplified by the National Library of Medicine’s use of subheadings.