Cook was with Macquarie Bank for 11 years, mainly in the Auckland office, but including 18 months in Wellington.
"From 2005 I was doing a lot of work in the retirement village sector because Macquarie looked at Summerset then, [and] when AMP bought it and we looked at it when the founders were looking to sell," he said.
"I'd known Summerset for a long time. The growth is very exciting and my parents are starting to think about a retirement village, so it does touch everyone.
"I'd known Norah and the team for a long time, so I had a lot of confidence in the business. I'm very lucky to be selected for the CEO position and to be honest, feel quite privileged."
However, he does admit to initially being shy about the top role.
"I thought, 'Why would I want to do that?' because I'd never thought about it. Then I thought about what we could do with the business."
Summerset now has 18 villages and forecasts development of 250 units this year, at least 300 annually "for a very long time after that".
As for criticism about the highly corporatised huge money-making business he said: "It's a good sign we make profits because it means we have a healthy business."
He was raised in Wellington, attending Rongotai College, then Victoria University where he majored in Latin and Greek "because I had a great teacher, Mrs Sue Randall at college. She taught me Latin".
Finding his career prospects limited, Cook moved north to Waikato University where he graduated with a masters in chemistry and had just begun a third degree, this time in commerce, when he saw Macquarie hunting for staff. He applied.
"I started a masters in finance and it was within three months that I got the Macquarie job in Auckland, answering the ad on the wall. Macquarie was looking for someone who was clever, hungry and going to work hard."
Cook was an athlete when he was younger but was frustrated to never win his races, often coming second or third. So he switched to discus and hammer throw events and in 1990s, was the NZ Highland Games champion and represented New Zealand at the Oceania Games where he was also the men's team captain, competing at Mt Smart Stadium in the hammer throw.
As for the Macquarie-Summerset switch, Cook said it was a big adjustment moving from multi-billion dollar banking deals to $2 million retirement village work but said he enjoyed working with the 600 Summerset staff, including 60 people at the head office in Wellington.
Cook acknowledged union agitation for higher retirement village worker pay rates for aged-care workers. He said it was ultimately up to the Government, which subsidises the wages of rest-home care workers.
"If we pay out of our profits, people in our retirement villages subsidise people in the care facilities. Village residents would have to pay for the rest homes. I don't think that's fair."
Asked why businesses like Summerset would not use profits for higher rest home worker pay, Cook said the business was sustainable as it was and there were no plans to change the model.
"So we're not apologetic about making profits. It's a sign we're doing something good. All our profits are reinvested in growth - building new villages and new care centres and without those profits we would not be able to do that."
Barlow said Cook was an outstanding person whose academic background displayed his intelligence, with merchant banking experience which was invaluable.
"He's an all-round kind of guy," she said.
Dave Roberton, head of equities at Macquarie, said people there were sorry to see him leave there.
"He was an excellent employee and led most of the thinking at Macquarie in the retirement sector in M & A so it was natural for him to go to a corporate. He was our expert on the investment banking team in the retirement and aged care sector. He was always the person we wheeled out when experts came from overseas. He had built up to associate directorship level. We were all sad to see him go because he was obviously very competent," Roberton said, adding that he was pleased to see Cook was doing so well.
And that nickname? The Hammer Thrower, of course.
