As many of you know, I worked in libraries for a long time. I am not a librarian, in that I don't have a Masters of Library Science degree. However, despite this, in some of my positions, I was somewhat involved in collection development, under the supervision of a librarian.
First, what is collection development? For sake of a quick and easy answer, it's how libraries decide which books to add to their collection. There is a LOT that goes into it, including patrons' demand and quality of the literature in question.
My first stint at collection development was when I worked part-time in the Cobb Library's genealogy and special collection room. We got a lot of donations. A LOT. Sometimes those books were great; a local genealogist had researched, confirmed, and compiled his family's history going back multiple generations, and offered us a copy of the completed book. Great! Someone else gave us a moldy copy of a county history we already had multiple copies of. Not great.
Moldy books aside, one of the things I did with the donations were to confirm that they were pertinent to our collection - genealogical resources, local (Georgia or Southeastern US) history resources, Georgia authors, etc. Once that was done, I looked them up in an international database to see if another library had catalogued it. If so, I printed this information and left the book for the department's head librarian to confirm as a candidate to add to the collection. Of course, she had additional criteria and made the final call, but in the time that I worked in this department, I helped add over 1,000 books and periodicals to our collection in that way.
When I worked at an academic library at a local university, my CD duties got stepped up a notch. By this time I had been working full time in the children's department at a busy library for a few years, and had much more donation processing experience under my belt, in addition to more understanding of how a healthy library collection grows. I was assigned to a new and recently funded project - creating a "popular browsing" collection for the smaller of the two campus libraries.
I was very excited. The campus I was on housed many of the STEM courses, as well as some niche creative majors like video game design and fashion technology. We had a very diverse population - more international students and non-traditional (23 years and older) undergrad students than our larger sister campus. We had a lot of requests for Sci-Fi, fantasy, anime, and YA books, as well as trendy authors such as George R R Martin (this was during the hey-dey of the Game of Thrones TV series).
As someone who also enjoys Sci-fi, fantasy, YA, and George R R Martin, this was right up my alley. Does that mean that I just ordered my "to read" list and have done with it? Oh, no.
I did a lot of research. I checked best seller lists and looked for announcements of the winners of awards (Pulitzer, Printz, Georgia Book Award, Nebula, and Hugo to name a few). I looked at reviews - not on Amazon, but in resources like Publisher's Weekly and Library Journal - publications intended to help librarians choose which materials to spend their limited resources on.
I made a color-coded excel chart (because, as anyone who has worked with me in the past ten years knows, of course I did). I had so much fun... but I also took it very seriously. I had a small budget, all things considered, and was constantly asking myself, is it worth the eight, fourteen, or twenty dollars to buy this book? Will our patrons read it?"
The opposite of collection development is what is often called "weeding." This means deciding what books to remove from a collection. What? Remove books? No, say it ain't so! Well, I know it sounds shocking (especially if you've read my Banned Books posts), but just as a healthy collection needs to have books added regularly, it also needs to be trimmed occasionally. Think of it as cutting your toenails. Or better yet, like pruning a tree or weeding a garden (which is why I like the term "weeding").
If you have a teenager looking for a book to read and they pick up a copy of a book with a super 80's-tastic cover, as opposed to something trendy and "lit" (am I using that right, you hip groovy cats?) they probably aren't going to read it. A water-damaged copy of a best-selling author is going to sit on the shelf untouched. A computer science student isn't going to get much help from "Computers and You: 1982 Edition." Your collection has to stay interesting. It has to stay in good repair. It has to stay relevant.
In my time at Cobb Libraries, I also helped with weeding which, once I got past the scandal of "you mean we might GET RID of some of these books?!" I found very interesting and even satisfying. Again, I was doing this under the supervision of a librarian. I had certain criteria and certain steps. Sometimes I was given a list of specific titles to pull to look into further. These were either older (potentially outdated) non-fiction, or books that hadn't checked out in a given period of time - usually five years, though sometimes shorter if it was pulling specific copies of books we would have had a lot of. When Harry Potter and the Prisoner of Azkaban first came out, the library got dozens of copies due to high demand. But if you have five copies out of 50 that haven't checked out in several years, maybe it's time to consider pulling some.
Of course, the first thing we checked was number of titles at each branch. If a small branch has three or four copies of the same book and there are larger branches that don't have one, you send it to another branch where it might get some new, interested patrons looking at it.
Damage was another consideration. If I pulled a book that was falling apart, missing pages, water damaged beyond minor staining, etc., I checked how many copies we had and usually set it on a pile for the librarian to confirm removing from the system. The exception was if it was the last copy of the book, or if it was a high-demand book (say, To Kill a Mockingbird) and we were concerned about not having enough copies.
And as for outdated, well, let's just say that if Indiana Jones would pick up the book and say, "This belongs in a museum," it should probably be weeded...
Also, weeding doesn't mean "throwing away." Books that we removed that were in good condition were sent to the book sale. Books in bad condition were sent to recycling. Irrelevant material (like bound copies of tech periodicals from the 30's that were available on the library's online database) were sold to film companies to use for props. I know some libraries even use weeded books as craft supplies.
Of course, as you would expect at a public library, sometimes public opinion tries to get involved in collection development - "why won't you add my self-published memoir to the collection?" "when are you going to get some copies of 50 Shades of Grey?" "When are you going to REMOVE 50 Shades of Grey?" This is why many libraries have a collection development team, a collection development policy (often available on the website, or, if not, in print upon request), and a weeding/request for removal policy. This is so when your lowly part-time shelver starts getting these questions thrown at him, he has a group and a policy to refer people to.
Recently I've been seeing more in the news about parents and politicians getting involved in trying to pull certain books from libraries, or bar others from being added. And while, to a certain extent, I do believe that parents should be involved in what their children read, pitching a fit and demanding that a book be removed when you've only read page 39 is not the way to go about it. What do you know about collection development? Where did you get your MLS degree?
Now, like I said, I'm not a full librarian. There are many library professionals out there who were far more qualified than I to choose books to add to a collection. But I like to think I gave it a good, well-educated, unbiased attempt. I even added books, or kept potential weeding candidates that I personally didn't want to read, or had read and hadn't liked. Just because I don't like it doesn't mean you shouldn't read it.