In the 1980s, Maurice worked with the British composer Oliver Knussen on a children’s opera based on the book, which was most appreciably performed on the Proms in the Royal Albert Hall in London in 2002. In 1983, Walt Disney performed a chain of computer-generated imagery tests, the use of Where The Wild Things Are as their subject. In 2009, a live-movement film version of the book was released, directed by Spike Jonze and with Maurice as one of the producers.