Former chief inspector of schools Sir Chris Woodhead, who had motor neurone disease, has died, friends said today.
The 68-year-old, who headed Ofsted for six controversial years until 2000 and had some fierce clashes with teaching unions, was diagnosed with the disease in 2006.
He resigned as chief schools inspector after a series of rows with then-education secretary David Blunkett.
Tributes from across the sector have been pouring in, including one from prime minister David Cameron, who tweeted about Sir Chris' legacy.
Current education secretary Nicky Morgan said that she was "saddened" to hear of the death of Sir Chris, who she called "an immense figure in the world of education".
"His determination to ensure that every child had the best education possible raised aspirations and changed lives," Ms Morgan said. "He was someone unafraid to speak his mind or challenge established orthodoxies and our education system is the better for it. My thoughts are with his family and friends at this sad time."