Conservative Party co-chairman Baroness Warsi paid tribute today to Tory peer and former Cabinet minister Baron Carr of Hadley, who died aged 95 on Friday.
As Robert Carr, he served as employment secretary, leader of the house and home secretary in Edward Heath's 1970/74 administration.
And he served for a week as acting leader of the Conservative Party during the election which led to Margaret Thatcher taking the helm in 1975.
Elected to the House of Commons in 1950, Carr formed part of the liberal "one nation" group and served as parliamentary aide to Anthony Eden as foreign secretary and prime minister.
He resigned from an early ministerial post for the world of industry in 1958, returning as chairman to the aluminium castings company - founded by his great-grandfather - where he had begun his career on the factory floor.
But he was back in government in 1963, as secretary for technical co-operation.
As employment secretary, he passed the highly contentious Industrial Relations Act of 1971, which provoked confrontation with the unions and foreshadowed many of the reforms implemented more fully by the Thatcher administration in the 1980s.
His homes in London and Barnet were targeted in 1970 by the Angry Brigade, a small group of anarchists who carried out a series of bombings before being arrested and jailed. Both properties were damaged but no-one was hurt.
As home secretary, he devised a National Security Plan to tackle the threat of terrorism from the IRA and Arab groups.
Carr was created a life peer in 1975, leaving the Commons to become a director, and later chairman, of Prudential Assurance.
Lady Warsi said today: "It is with great sadness that we learn of the death of the Baron Carr of Hadley.
"He was a true Conservative who served his party with distinction. Our thoughts and prayers are with his wife, Joan, and his two daughters."