The Education Secretary Michael Gove paid tribute to Lady Morgan for her "tremendous contribution" to the work of Ofsted.
She has brought great knowledge and insight, leading the board strongly through a period of significant change, both managing the smooth transition when there were changes in Chief Inspector, and leading the reforms to the inspectorate and its work.
I hope that she continues to play an active role in helping to shape the education landscape to improve standards for all children and young people.
Lady Morgan told The Independent: "Ofsted plays a crucial role in delivering independent inspection that is trusted by the public and particularly by parents. I am proud of helping lead Ofsted through a period of reform that has strengthened our inspections."
More top news
GPs have a public duty to tell authorities if a patient is driving against medical advice, new guidance from the GMC says.
The Government may be about to announce a new levy on council tax of up to 2% to replenish social care budgets.
How do you solve a £4.4 billion hole like tax credits? At 12.30pm on Wednesday, we'll find out.