Dame Paula was made a dame companion of the New Zealand Order of Merit in the New Year Honours for "services to the State".
She is leading a highly successful transformation as chairman of ACC, is deputy chair of KiwiRail and a director of Auckland Transport.
But it is her ground-breaking work leading social policy reforms, where she pioneered the "investment ethos", that currently makes waves.
As chair of the Welfare Working Group, Dame Paula led a revolution in the way the State approached sole parent beneficiaries by understanding their "customer needs" and taking a long-term view over the personal cost and cost to the taxpayer if outcomes were not changed.
"What used to be the Domestic Purposes Benefit but is now Sole Parents Support - we had seen that grow by 5-8 per cent per annum for decades," she says. "When we started it was approaching 90,000 people on that benefit and it's below 70,000 now.
It's not just about saving dollars - it's made a huge difference in the lives of people and their children.
That same "investment" ethos now guides the recommendations the Rebstock-led CYF panel made to Government just prior to Christmas.
"The one thing the investment approach tells you is the earlier you invest the more likely you are to be successful," says Rebstock. "For young kids it makes a lot of sense. If they are exposed to a lot of trauma throughout their childhood it is really hard to recover from that.
"The system has been geared to immediate safety concerns, yet we can identify who the vulnerable children are practically on the day they are born and we just need to invest in the better prevention and understand the nature of vulnerability.
"It isn't just about the immediate risk of physical harm. if you look right now at these kids a lot of them have physical and emotional abuse. Most of them will tell you the emotional abuse is the hardest to get over.
Rebstock is adamant that what young children need most is a loving and stable home.
"We know from the work we've done with the community that there are many families who would like to step up and we have to make to easy for them to do it.
"And that means they shouldn't be having to navigate through eleven different Crown agencies to get the services and support they need."
The Montana-born Rebstock - who left her Greenhithe home on Boxing Day for a lengthy sojurn on the family's Don Senior launch - had already let her Washington State based parents in on the secret. "You always wonder what they make of it not coming from a Commonwealth country," laughs Rebstock. "My mother said you mean like Dame Judi Dench?
Rebstock and husband Ulf Schoefisch met while studying at the London School of Economics.
"We finished there the year the stock market crashed," recalls Rebstock saying it ended their hopes of pursuing financial markets careers in London, "Someone told us things were booming in NZ, but when we got here the fallout had finally spread to New Zealand too."
Now a dual national, Rebstock landed a job in the social policy branch of the Treasury in the "Graham Scott era" which proved the foundation for much of her subsequent work.
Dame Paula does not shy away from controversy.
The Honour citation does not mention her controversial report into the leak of documents about restructuring plans at the Ministry of Foreign Affairs and Trade.
"The MFAT stuff was just hard and it needed to be looked ," says Rebstock. "Our democratic system relies on Ministers being able to trust officials to behave in a appropriate manner.
"It needed to be looked at and put to rest."
Dame Paula was particularly fearless when presiding as chairman of the Commerce Commission - the highlight of her career to date - where she faced down insidious opposition from elements in business when it came to tackling entrenched privilege.
"I think we put issues around competition and the importance of that to the economy and consumers on the agenda in a way it hadn't been," she recalls. "I loved that job - it's one of those things you can only do for a period.
"I was there for 11 and half years. It still broke my heart to leave even though it turned out I think to be the right time."
Dame Paula was made a companion of the NZ Order of Merit in 2009 for public services and was the New Zealand Herald's New Zealander of the Year in 2007.
