The American Library Association (ALA) defines a challenge to literature as an attempt by a person or group of people to have materials, such as books, removed from a library or school curriculum, or otherwise restricted. Merely objecting to material is not a challenge without the attempt to remove or restrict access to those materials. The ALA defines a challenge thus:
A challenge is an attempt to remove or restrict materials, based upon the objections of a person or group. A banning is the removal of those materials. Challenges do not simply involve a person expressing a point of view; rather, they are an attempt to remove material from the curriculum or library, thereby restricting the access of others.
According to the ALA, a successful challenge would result in a banning and removal of those materials, a form of censorship. However, the ALA agrees that materials may be removed from libraries in appropriate circumstances and Island Trees School District v. Pico suggested that books that are pervasively vulgar may be removed legally.
Challenges in the U.S. and Canada—tracked by the Canadian Library Association's Advisory Committee on Intellectual Freedom, and the Book and Periodical Council's Freedom of Expression Committee—are often brought by parents wishing to protect their children from content that they deem to be inappropriate or offensive. The ALA suggests that, while parents and guardians should have the right to determine their children's access to library resources, that right applies only to their children and no library policy, such as restrictive scheduling or usage policies, should deny children access to library resources.
The differences between challenging a book and banning were discussed by a columnist for American Decency who raised concerns that "efforts by parents to become involved in their children's education by raising questions concerning age-appropriate material" was being referred to as banning. Similarly, former ALA Councilor Jessamyn West said, "The bulk of these books are challenged by parents for being age-inappropriate for children. While I think this is still a formidable thing for librarians to deal with, it's totally different from people trying to block a book from being sold at all."
- "Censorship and Challenges". American Library Association. Retrieved 2011-06-16.
- "Support for dealing with or reporting challenges to library materials". American Library Association. Archived from the original on May 5, 2009.
- "Marking 25 Years of Banned Books Week," by Judith Krug, Curriculum Review, 46:1, Sep. 2006. "On rare occasion, we have situations where a piece of material is not what it appears to be on the surface and the material is totally inappropriate for a school library. In that case, yes, it is appropriate to remove materials. If it doesn't fit your material selection policy, get it out of there."
- Island Trees School District v. Pico, 457 U.S. 853 (1982).
- Challenged Books and Magazines, Freedom to Read: Book and Periodical Council (2009). Retrieved on January 9, 2011.
- "Free Access to Libraries for Minors - An Interpretation of the Library Bill of Rights". American Library Association.
- "'Banned Books Week' Stokes the Fire," by Cal Thomas, Muskegon Chronicle, 22 Sep. 1995.
- "Banned Books Week is Next Week," by Jessamyn West, Librarian.net, 21 Sep. 2006.
- Books Challenged or Banned in 2006-2007, Robert P. Doyle, American Library Association