In part five of The 9th Floor, Guyon Espiner talks to Helen Clark about her three terms in power as she sought to draw a line under Rogernomics, unleash new social reforms and rethink New Zealand's place in the world.

In part five of The 9th Floor, Guyon Espiner talks to Helen Clark about her three terms in power as she sought to draw a line under Rogernomics, unleash new social reforms and rethink New Zealand's place in the world.

Watch a video of the interview here.

By Guyon Espiner

When you think of someone who might embrace an offer of job sharing, Helen Clark doesn't immediately spring to mind.

But the idea of Winston Peters sharing the Prime Ministership over a term of government was "floated" with Labour in the failed attempts at deal-making after the 1996 election, Clark says in the final episode of The 9th Floor.

Clark says she can't recall who raised it, as during the coalition talks Peters often had others communicate for New Zealand First through "back routes".

She says she doesn't know how serious the proposition was and ultimately it was not the stumbling block which saw Peters reject Labour and form the first MMP government with National.

"It might have been loosely floated but that wasn't the sticking point. I think Finance Minister was the sticking point," she says. Regardless, the idea of sharing the top job wasn't one she could entertain. "No. You can only have one Prime Minister."

No one doubted who was in charge when Clark finally got the role in 1999. Once, when Deputy Prime Minister and Finance Minister Michael Cullen was asked what the government was going to do about some thorny issue, he replied: "Well, the government has gone skiing."

Clark enjoyed that memory when we raised it during the day we spent with her in Auckland, as she came home from New York for a brief Christmas holiday.

"That's a good line," she chuckled. But it's more than that. That story, and this interview, illustrate the degree to which the power of Prime Minister resides with the person, more so than with the office.

After researching and conducting interviews with five former Prime Ministers it's a strange feeling to realise that the job doesn't exist. There is no job description. You can take a chair of the board, consensus approach and delegate power to Ministers as steward of the Cabinet or you can be master and commander…

Go to this episode on rnz.co.nz for more details