Outwith Alistair Darling's circle of close friends he is a largely unknown quantity. He has risen through the ranks from the left to the centre of the political spectrum, making few enemies, fewer, if any, mistakes, and keeping his counsel largely to himself, and his nearest and dearest.

Those who say the former Edinburgh advocate is dull and boring reveal how little they know him or are prepared to find out. He is the most self-effacing of men, according to the people who know him best, and has a sharp and dry wit.

Thanking his wife, Maggie, for organising his surprise 50th birthday party, he looked around at the assembled guests, and said he felt as if he was attending his own funeral.

Not so long ago when the press turned up at his Edinburgh home, they were told he was not available - he was in scruffy jeans, working in his garden. At that point he appeared pushing a barrow, said hello and off they went. He wondered why they were there, and why they had gone. They thought he was the gardener.

Gardening is one of the great passions of his life, as is his boat on the west side of Lewis, his favourite holiday destination and the island on which his mother was born and brought up.

He treasures his time at home and relishes the home comforts provided by his wife, who before she gave up her career was, as Margaret Vaughan, a journalist with The Herald.

He adores his children, Calum and Anna, and is an indulgent, generous father. They dine out on the jokes they manage to put over on him, like the time they persuaded him to ask for a super, duper, hooper-sized Mac' knowing full well he would have no idea that such a thing did not exist.

His children keep him in touch and up-to-date, and its thanks to them he has added The Killers, Coldplay and Moby to the Beatles, Leonard Cohen, Pink Floyd, Mahler and Mozart, in his CD collection. They take no responsibility for him enjoying the Gaelic psalms written by his great grandfather.

He enjoys watching films and television: Yes Minister, Monty Python, Fawlty Towers and One Foot in the Grave are among his favourite TV programmes.

His reading tastes are catholic and either in London or at home he keeps up to date with modern fiction, political biography, and - first and foremost - history.

He will run a tight ship in the Treasury. Scottish colleagues remember how, when he was Chief Secretary to the Treasury in 1997, he would take them to task if an official car picked them up at Edinburgh Airport. In these days, before security limited his freedom, he would take the bus.

Friends say he is "ultra resistant" to anything that might be interpreted as corrupting. Offers of seat upgrades on planes are refused; and tickets to concerts, where he might be compromised, are turned down.

Ensconsed in the Treasury, Mr Darling will not be, as some say, Gordon Brown's poodle, but whatever differences they have, they will remain private. He will not brief against the Prime Minister.