1. The Harry Potter Series, by J. K. Rowling, for its focus on wizardry and magic.
2. The Alice Series, by Phyllis Reynolds Naylor, for using offensive language and being unsuited to age group.
3. The Chocolate War, by Robert Cormier (the “Most Challenged” fiction book of 1998), for using offensive language and being unsuited to age group.
4. Blubber, by Judy Blume, for offensive language and unsuited to age group.
5. Fallen Angels, by Walter Dean Myers, for offensive language and unsuited to age group.
6. Of Mice and Men, by John Steinbeck, for using offensive language and being unsuited to age group.
7. I Know Why the Caged Bird Sings, by Maya Angelou, for being too explicit in the book’s portrayal of rape and other sexual abuse.
8. The Handmaid’s Tale, by Margaret Atwood, for its sexual content.
9. The Color Purple, by Alice Walker, for sexual content and offensive language.
10. Snow Falling on Cedars, by David Guterson, for sexual content and offensive language.

The most frequently challenged authors in 1999 were Judy Blume, Robert Cormier, Stephen King, Lois Lowry, Chris Lynch, Walter Dean Myers, Christopher Pike, Phyllis Reynolds Naylor, J. K. Rowling, and Alvin Schwartz.

Note from the ALA: "Please note that the most frequently challenged authors may not appear in the list of most frequently challenged books. For example, if every one of Judy Blume’s books were challenged–but only once–not one of her books would make the top 10 list, but she herself would make the most challenged author list."