Alastair Campbell was appointed as Tony Blair's official spokesman in 1994.
From then up until the announcement that he was leaving his government post, the two men were regarded as so close that his words have often been interpreted as carrying the full authority of Mr Blair. Despite opting for a more behind the scenes role as communications chief in recent times, Alastair Campbell has proved that he is capable of making the news in his own right.
Alastair Campbell read modern languages at Cambridge. By the age of 29 he had moved a long way from his roots as the son of a Pennine vet to become the news editor of a newspaper called Sunday Today. But the publication's launch faltered and the experience led him to a nervous breakdown.
Alastair Campbell is said to have come out of the experience less brash, more disciplined and even more driven in his career. Around the same time he gave up alcohol - a step believed by many to give him the advantage of a clear head 24 hours a day to deal with the media.
His career in the media continued successfully and he soon became political editor of the Daily Mirror. During this time he was also one of then Labour leader Neil Kinnock's closest advisers.
It was from that post which Alastair Campbell resigned to become spokesman for Tony Blair, then leader of the opposition. With the Labour election victory in 1997, he became the prime minister's chief press secretary, setting up a formidable Whitehall machine to put over the government's views and try to control the news agenda.
In 2000 Alastair Campbell gave up daily briefings to Westminster lobby journalists to concentrate more on long-term strategy.
He speaks at corporate conferences on the media, politics, communications, strategy and change.