The former leader of the opposition gave his final speech in the debating chamber on Tuesday evening, where he reflected on 18 years in Parliament.
Mr Cunliffe says his belief has always been that "all people are created equal, therefore they all deserve equal opportunity, dignity and respect".
"Markets make good servants but bad masters, and it's the Government's job to make sure that the economy serves our people and not the other way around," he said.
"Inheriting the health portfolio a year before the general election was bound to be fun."
He recalled a story about senior doctors planning to go on strike in his first week with the portfolio.
"The strike was averted after a long liquid dinner in my Beehive office, with the DHB and senior doctor's representatives. The condition was no one was allowed to leave until the deal was signed, which was actually at 5:30am the next morning."
Mr Cunliffe said inequality is holding New Zealand back.
"The poor are getting poorer, the middle are working harder just to stand still," he said.
"New Zealand has become a speculators pavlova paradise. No capital gains tax, negative gearing, weak rules on foreign land bankers and throw in tax loopholes big enough to drive an apple through."
He acknowledged that his message didn't resonate with voters in the "bizarre" 2014 general election, or the "missing million" who didn't turn out to vote.
"I have no regrets for standing up for what I believe in, though I recognise my delivery could at times have done with some work. And no, family violence is still not okay."
Mr Cunliffe led Labour to its defeat in the 2014 general election, the party's worst electoral performance since 1922, achieving only 25 percent of the vote.
He was first elected to Parliament in 1999 as MP for Titirangi, and in 2013 he took over as leader of the Labour party.
He is joining the leadership team of an Auckland-based management consultancy.