Weeding and the Half-Life of Books

Weeding is a process in which librarians remove books from the library. (Karen Sawatzky wrote previously for SLAW on the subject.) Reasons for weeding include to remove materials from the collection that are no longer useful or that are actively dangerous. Weeding is also a good way of reclaiming shelf space, a particular concern in the era of shrinking library space.

Typical questions that librarians ask themselves when weeding a collection include:

  • Is there a newer edition of this title and do we own it?
  • Do we own anything more current on the subject?
  • Is the information available electronically? If so, is the electronic version a proper substitute for the print version? In some cases the electronic version of a publication omits images and diagrams found in the print version. Licensing restrictions may mean that using an electronic version of a publication is restricted to fewer people than if it were in print.
  • How much is the book used? Keep in mind that usage statistics may not give the full picture; use them in conjunction with user feedback.
  • What do users think of an item? When weeding it is important to consult users as to whether they consider an item useful. You may find that quality and usefulness are not the same thing; I have had a lawyer describe a book as “terrible” while noting that we should keep it since “no-one else has written anything better on the subject.” A side benefit of asking lawyers about less used items is that it reminds them that these resources exist and prompts them to use the resources in the future.
  • Is the book owned by a nearby institution? Keep in mind that these institutions may also be downsizing and decide not to keep the title in question. (Sarah Sutherland discussed this problem in greater depth in her SLAW article on “Where Will Old, Expensive, or Unexpected Legal Information Come From When Libraries All Downsize Together?”)
  • Is the information in the book still correct? If not, does the book have historic value? What’s the danger of keeping the book?

Most of these questions are fairly easy to answer. However the question of whether an older book is still valuable can be trickier to answer, particularly in the situation where information contained in the book is no longer correct. The value of an older book depends in part on its subject matter; a book on computer law is likelier to become obsolete more quickly than a book on maritime law. The purpose of the publication can also make a difference; for example, a newsletter that is published as a current awareness tool will have a much shorter shelf-life than a treatise on the same subject.

A book can still be valuable even if the information that it contains is no longer current. Researchers often need to know what the law was for a specific time period; for these kinds of questions, old copies of consolidated acts are helpful. Other older resources that can come in handy for historical reference include atlases and directories.

Finally, documenting weeding decisions should be part of the weeding process. In a recent article, Dunstan Speight suggests that in addition to recording that a book was discarded, you should record the reason why and who made the final decision. Similarly, if a decision was made to keep an old edition of a book, Speight suggests “record[ing] this information on the catalogue record and the reason why it should be retained” as this will be helpful when the next round of weeding takes place.


  1. If any weeding law librarian has a good, complete set of the English Reports to unload, please get in touch!