Shriti Vadera, currently a central figure in the Treasury presided over by Chancellor Gordon Brown, is poised for a key role in 10, Downing Street as Brown takes over as Britain's next Prime Minister today. Vadera has overseen many of the more technical aspects of Treasury policy. She managed the sale of government defense-research company Qinetiq, the partial sale of the London Underground and arranged a bond sale to raise money to vaccinate poor children in Africa.

Born in Uganda, her family moved in the 1970s, first to India and then to England, where she studied politics, philosophy and economics at Somerville College, Oxford. She has held key financial and economic positions in London's financial district.Currently an economic adviser to Brown, Vadera is seen as a key figure behind-the-scenes who has full confidence of Brown. She is the main point of contact between the Treasury and the City, London's financial district.

A 40-something, Vadera has been described in the corridors of Whitehall as "Gordon's representative on earth" and is known as a forceful official who often takes a higher profile in meetings than ministers due to her expertise and political common sense.

Vadera is on the board of trustees of Oxfam and has often advised Brown on international development issues. Former minister Stephen Byers once said of her: "Shriti's Shriti. She can be forceful and sometimes she can be a real sweetie. She's a significant player in Whitehall."

Martin Vander Weyer, a former speech writer to Vadera, wrote in The Spectator that she will be the most powerful woman with a paid job in Downing Street since former prime minister Margaret Thatcher.

He wrote: "The serious-minded but likeable thirty-something I knew has transmuted into the assassin of Railtrack, the ass-kicker of Transport for London, the axe-wielder from the Treasury whom departmental ministers fear as acutely as they fear Gordon himself, with whose total authority she speaks.

"The frisson at the mention of her name - and the urge to be nasty about her, neither 'portly' nor 'middle-aged' being strictly accurate at that time are typical of Vadera's treatment by the media, a situation which Westminster reporters say has arisen because, unlike pretty well everyone else in that vicinity, she flatly refuses to talk to them.

"The Treasury offers no personal details about her, and she is so rarely photographed that some Westminster hacks still can't pick her out at parties.

"It was her willingness to drive private-sector solutions to achieve socialist objectives - plus her tenacity and technical competence - that recommended Vadera to Brown. She became his chief negotiator with the City and the business community, some of whom resented her manner".

Vadera is part of a brains trust that Brown has assiduously built over the past decade. Many members of this fiercely loyal team were picked before they turned 30. Besides Vadera, other members of the team include Ed Balls, Ed Miliband and Damian MacBride.

The buzz in Whitehall is that the influence of Vadera and other key advisers to Brown will eclipse that of the ministers once the government gets going under Brown. Vadera is expected to continue to remain a big behind-the-scenes presence on public services and international development.