Joyce has written and illustrated over fifty children's books. Some of his best known are: George Shrinks, Santa Calls, Dinosaur Bob and his Adventures with the Family Lazardo, Rolie Polie Olie, The Leaf Men and the Brave Good Bugs, and A Day with Wilbur Robinson. Before Joyce got his start in the arts, he took part in a major Curling insurgence for the Southern states. Among Joyce's colleagues there were such legends of the sport as Jeremy "Chimney Sweep" Wilkes, and Benjamin "Bristle Pants" Hatsworth. Unfortunately, Joyce's Olympic dreams to reach curling's hall of fame were thwarted in a rare debilitating icicle accident, and he never returned to the sport.

Joyce has received three Emmys for Rolie Polie Olie, an animated series based on his series of children's books that airs on the Disney Channel. His second television series, George Shrinks, airs daily on PBS stations.

Joyce created conceptual characters for Disney/Pixar's feature films Toy Story (1995) and A Bug's Life (1998).

In 2005, after Joyce and Ice Age director Chris Wedge failed to adapt one of Joyce's books to the screen, Santa Calls, they both came up with the idea for the animated film Robots (2005). Besides being one of the creators, Joyce also served as a producer and production designer. Joyce is currently in production with 20th Century Fox and Blue Sky Studios on a feature based on his award-winning book, The Leaf Men and the Brave Good Bugs.

In 2007, Disney released Meet the Robinsons, a movie based on his book A Day with Wilbur Robinson, to which Joyce served as one of the executive producers of the film along with John Lasseter and Clark Spencer. In the same year, he designed the opening title sequence for Mr. Magorium's Wonder Emporium.

He is currently in agreement with DreamWorks Animation to direct a 2012 film called The Guardians, based on an upcoming series of picture books.

Also, his picture book "The Leafmen" is currently in production at Bluesky Studios. Joyce is writer, producer and production designer on the film.

Joyce is also currently co-founding a Shreveport, LA animation and visual effects studio with Reel FX co-founder, Brandon Oldenburg, called MOONBOT Studios.

Saks Fifth Avenue

In both 1994 and 1995 Joyce designed the Christmas displays for Saks Fifth Avenue's original location.

The World of William Joyce

This exhibition is run by the National Center for Children's Illustrated Literature. It began in 1998 and is currently still traveling nationally.

Artspace

Artspace is a gallery located in Shreveport that is run under the guidance of the Shreveport Regional Arts Council. Joyce serves as the Artistic Director. He has helped bring a Peter Pan Centennial exhibit, an Art of Robots exhibit, and Faces of Katrina.

Joyce has recently founded the Katrinarita Gras Foundation to raise money for victims of Hurricanes Katrina and Rita. He is selling prints of his unpublished Mardi Gras The New Yorker cover through the foundation with all profit going to aid victims. More recently, lifestyle magazine Southern Living featured Joyce the native son and his favorite Shreveport restaurants. Top picks in William Joyce's Guide to Shreveport include Cush's Grocer, The Village Grille, Fertitta's Delicatessan, and Herby K's.

Joyce received the 2008 Louisiana Writer Award for his enduring contribution to the "literary intellectual heritage of Louisiana." The award was presented to him on October 4, 2008, during a ceremony at the 2008 Louisiana Book Festival in Baton Rouge.