The company is based in Boston's Financial District. It was formerly known as Houghton Mifflin Company and changed its name following the 2007 acquisition of Harcourt Publishing. Prior to March 2010, it was a subsidiary of Education Media and Publishing Group Limited.

Formed in 1832 of the nineteenth century as a printing house, the company grew and diversified, playing an important part in the intellectual life of the United States through its purchase of a distinguished competitor. With time, Houghton’s focus shifted to more profitable educational publications, and it became a major presence in the educational market.

HMH is also home to media brands like Carmen Sandiego and The Oregon Trail; and brands including The Whole30; The Best American series; The American Heritage and Webster's New World dictionaries; Better Homes and Gardens; How to Cook Everything; the Peterson Field Guides; CliffsNotes; and many children's books including Curious George and The Little Prince; as well as publishing the works of J. R. R. Tolkien for United States distribution.

According to hmhbooks.com and en.wikipdia.org