The end of one year and the start of another brings the usual onslaught of lists. ALA committees produce a lot of them naming the best, notable, and award-winning titles. This magazine and other journals weigh in with their picks of the best books of the year. And while there is always some discussion, often lively, about which books did and didn't get honored or mentioned, for the most part, the librarians and editors who put together all of these lists do a wonderful and valuable job. No one building a youth collection could or should do without them.

That said, of course, it remains to be seen what the rest of us do about all of these recommended titles. I maintain that many answers to collection-development questions begin in your library, not in an ALA meeting. While the various lists represent the best books published in one year for the young adult audience as chosen by a group of informed observers, they may or may not indicate which are the best books for the customers you serve, or want to serve. While YALSA's Quick Picks come the closest to selecting books by (perceived) popularity, the function of these lists is to name the best books, almost always defined by quality. Moreover, none of these lists names the best books for their audience; they name the best "new" books for their audience.

Collection development isn't just about buying new books; it is about mixing new releases with standard titles. It is about weeding and maintaining, not just ordering everything on YALSA's Best Books for Young Adults list. It requires a balancing act between quality and popularity, single copies and multiples, old and new. By no means should these end-of-year lists be discounted; they are essential tools for anyone making purchasing decisions. My intent here is to shed light on the need for core titles in any youth collection, in particular those aimed at teens.

Since many YA collections aim for customer popularity, perhaps the most important lists that need to be consulted each year are not ones that come from journals or committees, but rather those generated by our own IT departments or circulation systems. The BBYA and other lists tell us what librarians and editors think are the books we need to buy to serve teen customers. The homegrown lists from our circulation systems give us a handle on what teens read, need, and even steal.

At the end of every year, but probably more often than that, youth librarians need to obtain reports on collection use, including:

• The items with the most circulation (raw numbers)
• The items with the highest turnover rate (ratio of circulation to number of copies)
• The items with the most reserves
• The items that are reported lost, damaged, and long overdue
• The items that are missing (aka stolen)

If possible, these lists should be searchable by collection (teen items) and by customers (checked out by teens). Not every circulation system can generate reports by user type or birthday, but since so much of teen circulation does NOT come from the young adult area, it is vital that teen librarians work with their IT department to gather this data without compromising privacy rights or setting up parameters that might limit access.

Of all of these lists, those that show you which books need to be replaced are most important. This list should give you a good idea of what books you need to purchase for your library. For example, one young adult librarian at a large urban library reported that in 2002 the titles most stolen included: Laurie Halse Anderson's Speak, Go Ask Alice, Amelia Atwater-Rhodes's In the Forests of the Night, Judy Blume's Forever, Meg Cabot's The Princess Diaries, Sandra Cisneros's The House on Mango Street, Lynne Ewing's Party Girl, Sharon Flake's The Skin I'm In, S. E. Hinton's The Outsiders, Annette Curtis Klause's Blood and Chocolate, Patricia McCormick's Cut, Walter Dean Myers's Monster and Slam, Louis Sachar's Holes, and Ellen Wittlinger's Hard Love.

While placing replacement orders may not be exciting, it is an essential part of every librarian's job. A core young adult title is one that has a reputation among teen readers, remains relevant years after its publication, is readable and accessible, and often has some edge or controversy surrounding it.

Supreme Court Justice Potter Stewart once wrote in reference to pornography, "...while I can not define it, I know it when I see it." You might say the same thing about a core collection title. In many cases, the call to include a title isn't based on hard data, but a "gut" decision based on a book's subject, style, graphic appeal, the book or author's reputation, and its availability. While there are certainly exceptions, a book's in-print status says something about its reputation and popularity. The question of where to shelve it, in a public library setting, then becomes the next sticking point.

A real core collection has to be a collection for young adults, not a core collection of young adult books in a YA area. It is not just a matter of semantics, but a shift in thinking about who drives collection development and the role, in particular in public libraries, of the young adult librarian. Developing a collection is customer focused: it does not matter that much to the teen where the book is shelved as long as the library owns it. In most libraries, this is much easier said than done. Collection budgets are broken down by materials, not customers. Some library systems won't allow for a book, like The Hobbit or a bio of Tupac Shakur, to be shelved in more than one part of the collection. If you are a young adult librarian, you must make sure that adult and children's collections contain those items that your patrons want and need.

Perhaps nothing demonstrates the wide scope of teen reading interests better than a series of surveys asking young people about their favorite books. One such survey was conducted at Teen Hoopla (www.ala.org/teenhoopla/) as part of the Young Adult Library Services Association's celebration of Teen Read Week in the fall of 2000. Teens were asked to answer the question, "What's the best book you have read this year so far?" Let's break down this list by broad types:

In 2001, YALSA teamed up with smartgirl.com to do a reading-interest survey, in which one of the questions was, "What's the best book you've read this year?" The top 15 answers broken down were:

In 2002, the same survey asked two questions: Best Book Read For Fun 2002 and Best Book Ever 2002. The results once again: core titles, not new titles, are what teens report on reading.

An isolated phenomenon? In the fall of 2001, the Hennepin County Library in suburban Minneapolis conducted a reading interest survey and asked, "What was the best book that you read last year?" The top 10 choices, broken down, were:

All of these reading interest surveys document three central premises: that a core collection for young adults is not just comprised of YA novels; that teens read widely from other areas of the library; and that the most popular items are not new, but tried and true titles. Librarians find out what to buy using reviews and best lists; teens find out what to read by browsing in stores and libraries, getting involved in book discussion groups, and hearing about titles from friends. To borrow from an NBC marketing gimmick from a few years back, an old book is new to teens if they've never read it before.

In these troubled budget times, our selection decisions carry even more weight as we slice up the shrinking collection pie. We still continue to buy books based on reviews and best lists; most of these core titles were new once and most appeared on these lists, but we need to remember that collection development is much more. With so many systems using centralized selection, developing these "core collections" might be one of the few opportunities left for librarians to use their neglected professional skills.

Nonfiction: Book of Mormon, Michael Brooke's Concrete Wave: The History of Skateboarding, Jack Canfield's Chicken Soup for the Teenage Soul, and Thia Luby's Yoga for Teens

Adult titles: Stephen King's The Green Mile, J. R. R. Tolkien's The Hobbit, John Steinbeck's Of Mice and Men, and Orson Scott Card's Ender's Game

Books for children/young teens: Phyllis Reynolds Naylor's Shiloh, Louis Sachar's Holes, Gary Paulsen's Hatchet (and sequels: Brian's Return and Brian's Winter), Lois Lowry's Number the Stars, and J. K. Rowling's "Harry Potter" series

"Pure" Young Adult: S. E. Hinton's The Outsiders, Avi's Something Upstairs, Sharon Draper's Tears of a Tiger, Carl Deuker's On the Devil's Court, and Lurlene McDaniel's Dawn Rochelle

Nonfiction: "Chicken Soup for the Soul" books, David Pelzer's A Child Called "It," Homer's The Odyssey, and the Bible

Adult titles: Megan McCafferty's Sloppy Firsts, Jerry B. Jenkins and Tim LaHaye's "Left Behind" series, Orson Scott Card's Ender's Game, and J.R.R. Tolkien's The Hobbit and "The Lord of the Rings" trilogy

Books for children/young teens: Lois Lowry's The Giver, Louis Sachar's Holes, Brian Jacques's "Redwall" series, Wilson Rawls's Where the Red Fern Grows, and Christopher Paul Curtis's The Watsons Go to Birmingham, 1963

"Pure" Young Adult: S. E. Hinton's The Outsiders

Nonfiction: Jack Canfield's Chicken Soup for the Teenage Soul

Adult: Orson Scott Card's Ender's Game, Harper Lee's To Kill a Mockingbird, and J.R.R. Tolkien's The Hobbit

Books for children/young teens: Sharon Flake's The Skin I'm In, J. K. Rowling's Harry Potter and the Sorcerer's Stone, and Louis Sachar's Holes

"Pure" Young Adult : Meg Cabot's The Princess Diaries, Caroline Cooney's The Face on the Milk Carton, and Philip Pullman's The Golden Compass