Power said in the news release that he was "looking forward to a new challenge and a new environment."
"This is the beginning of a new and exciting chapter in my career. One of my objectives after leaving Parliament is to contribute to the growth of New Zealand in the private sector and I feel that with my experience in working with and implementing change I can do that," he said.
Power's retirement was seen as a loss to the National caucus' liberal circle, but also as a key figure in the party to reach across the political divide.
His cross-party approach was been evident in a number of the 36 bills he got passed into law this term, many likely to have significant social impact.
Among those he was most proud of were on-the-spot police protection orders, and making illegal the code of silence that stonewalled police during the Kahui child killing case.
Asked he would have done differently in the past 12 years, Power said he would have voted for the civil unions bill and the 'anti smacking' legislation.
The pedantic management of time was something he learned in the lead-up to this term, when he had a month-by-month plan to drive his reforms.
"Some people go after the media, want to be in it all the time. That hasn't been my approach. Legislation is the tool I chose to deliver what I wanted to change."
-NZ HERALD ONLINE