New York: Random House, 2008. — unpageg : ill. — ISBN: 0394800788.
The book tells the story of Horton the Elephant, who, while splashing in a pool, hears a small speck of dust talking to him. Horton surmises that a small person lives on the speck and places it on a clover, vowing to protect it. He later discovers that the speck is actually a tiny planet, home to a community called Whoville, where microscopic creatures called Whos live. The Mayor of Whoville asks Horton to protect them from harm, which Horton happily agrees to, proclaiming throughout the book that "a person’s a person, no matter how small."