James Shaw has had no contact with Winston Peters since Thursday night's coalition announcement - but insists that isn't a sign of what's to come.
Mr Peters announced New Zealand First would be forming a coalition with the Labour Party, with Mr Shaw's Greens supporting the Government through a confidence and supply agreement.
It means the Greens will not be a formal part of the coalition, but will still hold ministerial roles outside of Cabinet.
Mr Shaw told The AM Show on Friday despite a turbulent relationship with Mr Peters in the past, a lot has changed.
"A lot of water has floated under the bridge in the last 12 years. I think [he's] changed as a person. A lot of our personnel have changed in that period of time as well.
"The people who were around [during the Helen Clark government] actually say that he worked really well, he was constructive, he was diligent, very professional."
Under Helen Clark, Labour shunned the Greens in favour of NZ First. But Mr Shaw says those who worked with him at the time "found him pretty solid to work with as a minister".
"I take their word for it."
In June he told the show working with NZ First "wouldn't be his first choice", but he "would if he had to".
He now says he's "really looking forward to building a constructive relationship with him".
Mr Shaw says the Greens are "absolutely delighted to be in this position" as they prepare to take on ministerial roles for the first time in their 27 years.
"They will be in areas that we campaigned on and that are important to us and the people that voted for us."
Those areas include making the country "a world leader against climate change, to store and replenish our forests and birds and rivers and to end child poverty".
"So what you'll see when the new Prime Minister makes the announcement is that we'll have a suite of portfolios that are related to those areas."
Mr Shaw was also pleased the new arrangement gives the party "a bit more leeway to move" - but insists they've committed to three years by Labour's side.
"If you look at the history of MMP in New Zealand it's littered with small parties that have gone into Government and haven't quite made it out the other side, so that did weigh quite heavily in our considerations."