One of libraries’ most important tasks — in the past, present and, presumably, future — is to help users save time in finding similar materials on a given topic. And whether library users realize it or not, subject headings remain one of the principal ways that libraries perform this key function.

First, a crash course for the uninitiated: subject headings are labels that provide a descriptive category for a given resource, whether that resource is a book, article, film, archival document or pair of socks. These labels can in turn be used to find similar books (articles, films, socks, etc.) because they now have a common language that’s been used to describe them; instead of some people looking for “cars” and others looking for “automobiles,” everybody’s now looking for “motor vehicles.”

What’s more, now that we’re in the digital age, items that are cataloged with the same subject heading are now just a click away; in this respect, they’re the obvious forerunner to Twitter hashtags. In a best-case scenario, a user can find an item that has a given subject heading — say, “psychoanalysis in literature” — click on it, and then find more items cataloged with that same heading, just as they can on Twitter, or on many blogs. I teach this technique to students in library workshops all the time, and once they know about it, their lives are never the same. (I exaggerate, but only somewhat.)

But just like all labels, subject headings can also have their pitfalls. I found this out recently in a stark way when I was teaching a workshop for a Film Studies course, and using the film Frozen River as an example. The film is a treasure trove of potential research topics, touching on rural economic hardship, single mothers, Native American tribal issues and immigrant border crossings. And so to demonstrate how to find an item on the topic of undocumented immigrants, I spotted an item in the catalog that seemed to relate very closely to this topic. I clicked on it to find the item’s subject headings and discovered that there is indeed a subject heading that relates very pointedly and directly to the issue at hand.

The problem? That subject heading is “illegal aliens.”

And so here, then, is a librarian’s Scylla and Charybdis: one the one hand, we have a label that can help users find more materials on the same topic — something that, at least in theory, helps promote access to materials, which is always the librarian’s watchword. On the other, the label in question uses language that many find to be problematic at best, and downright insulting at worst — and therefore may inhibit the very access the label was trying to provide.

Because as handy as they are, labels can oversimplify, and labels can limit. They can make it harder for diverse groups of people to feel welcome, to feel like they truly belong — the last thing that libraries and librarians want. What of the student whose friends or relatives include undocumented immigrants? What of students who are undocumented themselves? I can imagine they’d be very wary of using a library whose catalog appeared to call them “illegal aliens.” And who could blame them?

Simply put, it matters what we call things, and the library profession needs to make sure its descriptions promote, and do not discourage, access. Incoming students this year read Claude Steele’s Whistling Vivaldi, which provides solid evidence that negative labels contribute to a “stereotype threat” that keeps persons from achieving all that they might. It doesn’t take a huge imaginative leap to think that persons confronted by a description of themselves as “illegal” might be susceptible to this form of subtle discrimination. This potentially harms such persons’ education — their very ability to take advantage of the resources that a college can provide.

But at the same time, we can’t really do without labels, and so the library profession — which, truth be told, often does do a good job of advocating for equality of access to materials — really needs to do everything it can to make sure those labels do not give insult. Because subject headings that are used locally have to be in line with national and international networks, it requires approval by committee at the national level to change them. In 2014, a student group from Dartmouth College brought a proposal to change the label before the Library of Congress’s cataloging committee (check this link); unfortunately, it was not approved on grounds that we might call “legalese”; “illegal aliens,” in the view of the committee, was the sole truly precise legal description of such persons. (In response, a fellow librarian tweeted that the decision was “an embarrassment to our profession,” and really, I couldn’t agree more.)

So let this be a lesson to all those using subject headings — which, unequivocally, I encourage all researchers to do. They’re incredibly useful, but as with any other human-created, socially constructed entity, they’re imperfect. They can greatly narrow searches, winnowing down to only those items that are truly about a topic at hand. They’re also the specific products of a social milieu, and as such, they reflect the mores and sensibilities of a particular place and time. Because of this, they’re changeable, even if that is difficult and slower than many of us would like. So take full advantage of subject headings, and let us know if you need help doing that. Equally as important, let us know if you find a subject heading that you think could use some revision. Chances are that we’ll agree.

—Fred Folmer