Tony Lucki, a 30-year veteran of the educational publishing business, has announced his retirement as chief executive of Houghton Mifflin Harcourt, shortly after the group agreed to renegotiate $4.3bn of its $6.7bn debt load.

The departure later this month of Mr Lucki, 60, will leave Barry O’Callaghan in direct operational control of the main asset of Education Media and Publishing (EMPG), the group he built up through the 2006 and 2007 acquisitions of Houghton Mifflin and Harcourt.