She used to make big calls as New Zealand's leader. Now the problems she deals with come on a global scale.

There's a good reason former Prime Minister Helen Clark doesn't miss political combat now that she's in New York to head the United Nations Development Programme.

"You see I'm not really out of it," she tells the Herald on her visit to New Zealand this week.

"You've got to stand your ground in the UN system and I'm in a position to stand my ground. You've got to fight your corner, very much so."

"It's not all love and cuddles. There's a lot of turf wars and patch protection. Others encroach on one's organisation's mandate. What a surprise!"

Since March last year, Clark has been head of the United Nations Development Programme, the biggest of the UN's 27 agencies.

"Like BHP is the big Australian, we are the big agency."

As well as heading the big development agency, perhaps her biggest challenge is heading the group that co-ordinates the 27 agencies - including the Food and Agriculture Organisation, the World Health Organisation, World Food Programme, the International Labour Organisation, Unesco - and trying to get better co-operation among them.

Her description to Thursday's foreign affairs select committee meeting in Wellington of her drive get a more holistic and coherent approach to the development system, challenging the "silo" approach, sounds like an international version of whanau ora, I venture.

"I hope not!" she says in the back of the Crown car whisking her to Wellington airport.

She keeps a close enough eye on domestic politics to know that a former Labour Prime Minister would not accept that as a compliment.

As for John Key's present popularity, she can empathise.

"There's a lot of excitement about the new Government and so on but I can't complain about it - I got a great run too, for quite a long time."

Many former Labour colleagues attended one of the two formal functions in Auckland on Wednesday where Clark first received the Order of New Zealand at Government House - and later a honorary doctor of laws degree from Auckland University.

As with most things she does, a good deal of planning went into the guest list. She did not see the investiture as an intimate occasion just for close family and friends.

"I just thought as I have been PM, you'd expect an investiture ceremony to be somewhat reflective of your life, so I invited a broad base of people that I've worked with."

They included the leaders of all the parties she had worked with in government: Jim Anderton, Winston Peters, Peter Dunne and Jeanette Fitzsimons.

Tomorrow she flies back to New York. Her headquarters is across the road from the United Nations buildings on the edge of New York's East River.

In a typical week, she heads over to see Secretary-General Ban Ki-Moon two or three times a week for various meetings.

That's when she is in New York. She travels extensively, to both keep donor countries on-side, a particularly important task in light of the global recession, and and to oversee her own organisation's work.

Would she like Ban's job one day?

"Well I've never had any aspiration for that and when I went up to this position it was with his blessing and his support and I regard myself as a very loyal person in a position where it is important to support him to do the job."

She counts among the blessings of her new job the fact that she can focus on with the business at hand without the distractions of what she calls the "absurd and sublime" small bushfires in politics that can blow up into major headlines.

"We are not cursed with that."

Being a former prime minister helps to open doors for her to leaders and ministers, - more so being a former leader of New Zealand "which has no enemies, is well thought of. We did so much to position New Zealand as a country that everybody could deal with, everybody could work with, so that has been a tremendous help.

"You are not bringing any baggage."

The greatest exposure Clark had internationally in the past year was her arrival in Haiti soon after the earthquake.

She looked drained after inspecting the devastation first-hand, including the site where at least 90 United Nations staff were among the 200,000 killed.

Clark explained to the select committee meeting why top-rate aid agencies such as the International Red Cross and the World Food Programme were not getting aid in fast.

"Port au Prince would probably remind you of New Plymouth airport," she said.

It was used to about 12 flights a day, probably less than New Plymouth. All of a sudden it had to cope with 150 flights a day wanting to get in and with the control tower having collapsed.

She also talked about the opportunities for rebuilding Haiti.

Clark shared a platform with former US President Bill Clinton at the World Economic Forum in Davos, Switzerland, in late January where he made the case for investment in Haiti. Clinton is the UN Secretary General's special envoy to Haiti.

A few days earlier, Clark had shared a platform in a Montreal conference on the Haiti disaster with US Secretary of State Hillary Clinton, their first meeting.

It was Clark's idea to fly to Wellington to brief the select committee. She does it in other countries, so why not here?

It was a committee she chaired from 1984 to 1987 as a second-term MP. The present chairman is National MP and former diplomat John Hayes, a former High Commissioner to Papua New Guinea.

The committee heard about the new "South-South paradigm" that is emerging where developing countries such as China and India are becoming big players in development themselves and in some cases are seeking the help of UNDP to improve their development policies.

Fresh in her mind was a visit earlier in the week to Papua New Guinea, a desperately poor country "on the cusp of tremendous opportunities" with vast new wealth about to flow from liquefied natural gas exploration.

Clark said all that wealth could be a curse for PNG or a blessing.

"In the UN system, we are here to ensure it is a blessing."

She has offered UN support to help PNG design a sovereign wealth fund and then to help advise how the investments in education and health could transform the prospects of its people.

She told the committee she was "shattered" to discover in a recent survey of 11 provinces that only 36 per cent of children went to primary school.

At present PNG has more than 1000 individual aid projects. It is perfectly poised for a new approach to its development.

And Clark, as a longtime friend of Prime Minister Sir Michael Somare, is well placed to offer UNDP's support in getting a more co-ordinated and long-term approach to development.

From all the new bag of acronyms Clark is armed with in her job, the MDGs are the best used.

They are the Millennium Development Goals - eight of them to be achieved by 2015 to help eliminate poverty, improve health and education, and promote gender equality.

They are Clark's responsibility at the UN.

PNG is not on track to achieve any of them.

On a global front, the goal to reduce the number of people who are chronically hungry has gone up by 150 million in the past two years to about a billion people.

Clark will play a key role in a September summit at the UN to try to focus the minds of world leaders on the MDGs. She is trying to get a good attendance by leaders, including John Key. "It would be great if he came."

She was in her first year as Prime Minister, in 2000, when she flew to a summit in New York to sign the Millennium Declaration.

"I never thought in my wildest dreams I would come back as administrator of the UNDP with a particular responsibility for them."