You can see immediately why the Baroness Margaret Jay of Paddington has a way with men. At 65 she is still beautiful, with a glow that's even girlish at times. She is elegant, bordering on sexy, packed with well-controlled energy. And, as you would expect from the woman who presided over the removal of hereditary peers from the House of Lords, she is as tough as granite.

The baroness doesn't like the word tough. In England it is a word with negative connotations when associated with women. Later, however, describing the way she helped drive through the Labour Party's agenda for the peers, she gets into her stride: "It was very tough, a very tough political fight, very exhilarating, involving a lot of wheeling and dealing. It was 1999 and we took away their automatic right [to a seat in the House of Lords]. And they didn't like it at all. It was like the French Revolution had broken out."

In 2001, having achieved her aim, the baroness stepped aside as Leader of the House of Lords and Minister for Women in Tony Blair's Government and moved on. As she says, if you don't make these moves by the time you are 60 there is a chance it could be too late.

"I didn't want to go on being a leader - it was like being head girl of the institution. And I knew if I stayed on till this year [and the British election in May] I'd have been too old to do some of the things I've done in these last five years."

There was also the exhaustion factor. "One of the tough things about government is the amount of energy and drive you have to apply to it."

Plainly she was not written off as too tired. She was instead snapped up as a person at the top of her game. Now, in addition to being a member of the House of Lords, "and very much involved in the political scene in Britain", she is chairwoman of the Overseas Development Institute (an NGO which looks at poverty issues, debt and trade), a member of the Committee on Standards in Public Life, a non-executive director of British Telecom (BT) and the Independent News & Media Group (INM) and a member of Sir Anthony O'Reilly's Independent International Advisory Board. In the last three jobs, she is the only woman on the boards.

With the different jobs, go different names. She goes by her former married name, Jay, in business life, reserves the baroness title for the House of Lords, while in private life "I call myself by my married name [Adler]."

The daughter of former British Prime Minister James Callaghan, she was "raised to the peerage" in 1994, an honour which she carries lightly. As she says, "You have to be 'of somewhere', and most lifetime peers choose the boroughs where they live". She chose Paddington, which is not just her home, but that of the children's book character, Paddington Bear. And she laughs recalling how local children called her "a bearess".

It is her abiding interest in the media and world affairs that brings her to Auckland. A former journalist with the BBC in London, who worked on Panorama and This Week, before moving into politics, her position on the INM, plus the Independent International Advisory Board, is a good fit. She obviously enjoys bringing her particular take to the high-powered, male-dominated, 17-strong advisory board, headed by legendary former Washington Post editor Ben Bradlee.

The Callaghan family, with its strong Irish connections, had known O'Reilly for around 40 years. "We were looking for a holiday house in Ireland," says Jay. "The family was mad about sailing and we asked him [Sir Anthony] where to go. He suggested a village called Glandore in southwest Cork." The Callaghans found their house, not far from O'Reilly's. Now, says the Baroness, "When Tony introduces me to anyone, he says, 'This is my neighbour'."

Does she bring a different point of view to the male-dominated environments in which she operates?

"I don't believe in a feminist agenda," says Jay. "But I do think that [as a woman] you have a different take, a different chemistry."

For example, she says, "Although there were some strong women writers on the Independent in London, they weren't really getting a fantastic amount of prominence. I think Amanda Kennedy [the other woman on the London board of INM] and I have managed to give that a bit of a push."

Other special interests include world poverty, climate change, HIV and Aids, the role of women in modern society, the media and, of course, politics.

"It's terrifying, isn't it?" she says, when asked about global warming. "These are the two big things - poverty and climate change - that the UK Government wants to have an influence on at the G8. What we're trying to do is get the States to go along."

Her different chemistry, plus a birthright that landed her slap in the middle of British politics, has produced a life that has never been dull, including a highly publicised affair with Watergate reporter Carl Bernstein, which was later the subject of a novel and film.

Her father was Labour Prime Minister of Britain between 1976 and 1979. Her mother, Audrey, stayed at home with their two children.

Jay herself has worked all her life, including when her children were small, which gives her a particular interest in the pressures on working mothers. "The biggest social revolution in my lifetime is the rise of women with children who go to work."

Issues such as enough quality child care exercise her. "Where we've tried to make a difference is in the first few years," she says. "Better maternity and paternity pay and leave for parents. Now dads get some paid paternity leave and it's gone up since we introduced that."

Britain has also introduced tax credits for child care. "My eldest daughter, who works for the BBC, says she's had two children with the BBC, meaning she's had almost two years of paid leave."

The thing that's very "difficult to crack" is flexible work hours. She describes one of the small triumphs in the nursing profession where surgeons, who habitually started operating at 8 in the morning, were persuaded to begin at 9.30 when nurses who had children could get there. "And the women came back! It's not rocket science, just about effective management."

The even bigger problem she grapples with is how Britain will support the huge number of people of pensionable age due to retire in 20 years' time. "It's becoming a real issue," says Jay, whose own parents died in March within 11 days of each other, both at the age of 90 plus.

Despite the impeccable professional record, Jay is possibly best known for her 1979 affair with Watergate journalist Bernstein, whose then-wife, novelist Nora Ephron, was seven months pregnant. Ephron reacted by writing Heartburn, a novel based on the affair and subsequent break-up of her marriage. Loaded with fattening recipes and thinly veiled attacks on Jay, it was made into a reasonably successful movie.

Ephron went on to become a successful screenwriter, producing the original screenplay for movies including, Silkwood, When Harry Met Sally and Sleepless in Seattle.

Jay had been married to Peter Jay, a former BBC economics editor, who was then UK Ambassador to Washington They later divorced, after 18 years of marriage. In 1994 she married Aids specialist Professor Michael Adler. Together they have five children, Adler's two daughters, who are in their 20s, and Jay's three: Tamsin, 40, who has produced two grandchildren; Alice, who works in human rights ("She's actually in Laos at the moment"); and Patrick "who, I guess, has the most Irish genes and works for Ladbrokes. He's a whizzkid with figures."

Her husband has been in New Zealand too, sightseeing in Te Anau and Doubtful Sound. Typically, while he was doing that she had been at a business meeting in San Francisco. They met in Christchurch and she explains their subsequent drive through to Wellington, including a stop for whale watching at Kaikoura and wine tasting at Cloudy Bay before hitching a ride back to Auckland on Sir Anthony's private jet, was all part of her new agenda.

One of her motives in stepping down from the leadership of the House of Lords was to get more balance and she is working hard on the leisure part of the equation. "I think, increasingly, I don't feel that absolute drive," she says. "I want that balance in my own life, so I can go to the meetings but there's time to go and see the whales as well."