Margaret Hamilton Books, a children's publishing house established by Margaret Hamilton, was launched at the end of July 1988 with the publication of its inaugural title, Who Killed Cockatoo?. This was a new edition of a book by W. A.Cawthorne, first published in 1862, with new illustrations by Rodney McCrae. (Sheahan-Bright, p. 233.)
'During the 1990s Margaret Hamilton Books annually published about ten picture books and novels. Believing that "the hardback picture book is where aesthetic power lies", they published award winners (such as The Very Best of Friends by Margaret Wild and Julie Vivas [1989], and a body of work by Patricia Mullins).' (Sheahan-Bright, p. 250.)
In 1996, Margaret Hamilton Books joined Scholastic, the world's largest children's publisher, initially on a five-year contractual basis. In late 2001, when the contract expired, Hamilton sold Margaret Hamilton Books outright to Scholastic. (Sheahan-Bright, p. 250.) Today, Margaret Hamilton Books survives as a Scholastic imprint.
Source: Robyn Sheahan-Bright, 'To Market, To Market: The Development of the Australian Children's Publishing Industry', PhD thesis, Griffith University, 2004.