Spokesman Josef Blumenfeld confirmed to The Associated Press on Tuesday that Becky Saletan has resigned, but declined further comment. Saletan didn't immediately return phone and e-mail messages from the AP.
Saletan had served in the job since January 2008, when she was appointed to head the newly merged Harcourt and Houghton Mifflin divisions.
The company has been in the news for an alleged hold-down on new books. Blumenfeld has offered conflicting statements, saying the publisher of authors such as Philip Roth and Guenter Grass had "temporarily stopped acquiring manuscripts," but later acknowledging the policy didn't apply to education and children's books and a mystery book imprint.
Houghton Mifflin Harcourt has reportedly been hit hard by the tight credit market and any halt on acquisitions is widely believed to be in anticipation of a possible sale. Their owner, the private-equity concern Education Media and Publishing Group, has acknowledged that rival publishers have expressed interest in buying HMH.
Saletan, ironically, had initially benefited when Houghton purchased Harcourt last year. Formerly publisher of adult trade books at Harcourt, she was promoted to head the combined adult trade divisions, winning out over Houghton publisher Janet Silver.
Silver, who edited Roth and Cynthia Ozick among others, soon left to join Random House Inc.'s Doubleday division as an editor-at-large. She was among 16 employees laid off by Doubleday last month.