MMP's flaws and features will be scrutinised in a review of the electoral system, with public feedback to be sought from February.
The official results of the referendum on MMP were made public on Saturday, revealing that 56 per cent of people wanted to keep the system, while 41 per cent wanted a change.
The Electoral Commission will now lead a review of the system, to be conducted in two stages. The first begins in February when there will be a call for submissions, followed by public hearings in April and May.
A proposals paper will be available in August for public comment before the commission gives its final report to the Minister of Justice, Judith Collins, in October.
As well as the proportionality of the system, the review will consider the more contentious aspects of MMP, including the thresholds parties must achieve to win a seat, and dual candidacy.