As David Cameron chairs his last cabinet meeting on Tuesday, Theresa Villiers pays tribute to his work as Prime Minister below:
"Attending David Cameron's last Cabinet meeting today felt like the end of an era. I was one of the first few MPs to back David Cameron as a leadership candidate almost exactly 11 years ago when few people had heard of him. So I was there right at the start of the Cameron project and today I saw it start to draw to a close.
David Cameron will be much missed. I was very sad to see him announce his resignation. I am incredibly grateful to him for all the opportunities he has given me to serve in his senior team for over a decade - first in his Shadow Cabinet, then in government and then, for the last four years, in Cabinet.
It has been an honour to sit round the Cabinet table with him. I am certain that history will judge David kindly. He has been a great reforming Prime Minister.
He transformed the Conservative Party, bringing us back from years in the political wilderness and turning us into a party which was at home in modern Britain and capable of inspiring the confidence of the millions of voters we needed to get us back into Government. He won a general election last year which no one believed was possible.
He has taken on the challenge of welfare reform - something that for decades, successive Governments have failed to do. He has created a revolution in the way schools in England are established and run. He has rescued the economy from the ruins left by Labour and repaired the public finances during the biggest financial crisis for half a century. He has been steadfast in his commitment to the NHS, to our armed services, and to the huge efforts being made to combat the terrorist threat and keep people safe.
He has been incredibly supportive to me in my work first as Shadow Chief Secretary to the Treasury, then Shadow Transport Secretary, then Rail Minister, and then Secretary of State for Northern Ireland.
He has always strongly supported Northern Ireland. Under his leadership we have secured two historic cross-party agreements - Stormont House and Fresh Start - and delivered unprecedented political stability. David's response to the report on Bloody Sunday was a hugely significant event and has made a lasting contribution to long term peace and stability in Northern Ireland."