It was quite by accident that Jonathan Smales went from environmental activism to property development.
Greenpeace's London offices were bursting at the seams and Smales, the then-managing director of the UK arm, was contemplating the organisation's fourth move in five years.
"So I decided to find an old building in London that we could convert to become our new headquarters and I hired a couple of architectural students, gave them each a bicycle and sent them riding around North London to find us a build that was suitable.
"In the end we found a lovely old building which had been an animal testing laboratory, rather perversely and good karma for the building in a sense, and we did what turned out to be the first green office building in London."
That was back in 1989 and Smales admits they really didn't know what they were doing. "I really like the tangibility of building and working in design."
The second thing he discovered was that, in contrast to the "moaning and groaning" coming out of the building sector, it was easy to incorporate environmental sustainability principles into the building.
To the credit of Smales and the team of architects, engineers and designers who worked on the project, the building still houses Greenpeace today.
It was enough to set Smales on a path of sustainable development that has seen him work on a range of projects, including the post-event master plan for the London Olympic Games infrastructure.
It's culminated in the establishment of Human Nature, a real estate company with plans to fund and be master developer of a portfolio of sustainable development projects.
"Who would have thought 30 years ago that I would become a real estate guy."
He's still definitely an environmentalist. "I think that the way that we plan, design, build and run our cities is the most important environmental thing we do and, therefore, if you want to safeguard the environment, while improving people's lives, running great cities and great neighbourhoods is the key."
In the past cities were seen as dark, dangerous and evil places, Smales says.
But by the early 2000s attitudes were swinging around to see that cities - if they were compact and liveable - could be the most efficient places for people to live.
"[Cities] used less land, it was easier for people to move around, to meet one another, the massing of buildings was an inherently energy efficient thing to do and so the environmental virtues were beginning to be seen. That was the turning point."
While the practices of environmental sustainability in office and residential building design are now commonplace, Smales says the new challenge is to take that out to the streets.
Neighbourhoods and infrastructure are what make a city but the problem is cities have been allowed to sprawl to the point of inefficiency.
Mixed-use neighbourhoods where work, education and retailing are close to the front door is the best way to address the issue, he says, and it's not a new model.
Older, traditional neighbourhoods have people living above shops, with the doctor around the corner and work not too far away, says Smales.
"I don't want to be too romantic but we just haven't planned places like that for 80 years now, since the advent of the motorcar really.
"We thought the car would give us ultimate freedom.
"It's given us many freedoms but it's also changed the urban fabric in such a way that we are now dependent on cars.
"One of the things that we need to do is when we are regenerating is how do we bring a mix of uses into a place so that a place becomes a bit more self-contained, where you can fulfil your daily needs by walking down the street to the centre rather than having to drive for 40 minutes."
In New Zealand as a guest of Auckland City Council's redevelopment arm Panuku Development Auckland and the Government energy efficiency agency EECA, Smales says building sustainability into urban design doesn't need to come at the cost of profitability.
The key is a partnership between the public sector setting the long-term sustainability agenda, providing supporting infrastructure and de-risking projects to enable private investors to create higher-quality developments while still maintaining profitability.
"I think it has to be a public-private partnership. I think some of the social agendas and the risk profiles are too great for the private sector."
The public authorities that encourage businesses to do this will be world leaders in the future, says Smales.
Locally, Panuku Auckland Development's highest profile project has been the redevelopment of the Tank Farm industrial port area into Wynyard Quarter, a 20-year project with environmental sustainability hardwired into every aspect of the mixed-use area.
Fourteen projects are under construction with the area expected to grow by some 2000 residents and 11,000 workers in the next five to 10 years.
Back in London, Smales says word is getting out that Auckland is becoming a more liveable city and the environmental agenda is being taken more seriously.
Personally, Smales is putting his money where his mouth is with a mixed-use regeneration project on a former industrial site in the city of Norwich.
Bordered by three rivers, the brownfields site near the city centre will eventually have 1200 new homes, generate its own renewable power and heating, be criss-crossed with cycle and pedestrian connections and have workplaces in the mix.
"You need to show with your own work that these things are economically viable, not just fantasy projects otherwise it becomes a sort of elusive bureaucracy really."