Political editor Audrey Young looks at five factors that may play a part in Bill English's reshuffle today at3 pm - watch it Live on NZ Herald Facebook.
Rankings are rarely referred to between cabinet reshuffles but they really matter to ministers.
A rise or fall in the ranks can be a way of rewarding ministers and giving them a signal they are on their way out.
Ranks are an internal status symbol and determine a minister's seating position in the House and which level of the Beehive a ministerial office is assigned. Being No 8, for example, as Attorney General Chris Finlayson has been, mean being tucked in close to the Speaker's chair and out of the view of the Press Gallery, whereas being No 9, as Transport Minister Simon Bridges has been, gives him a seat near the middle of the chamber and the centre of the action.
Rankings can have practical effect as well in determining who is Acting Prime Minister.
Not long ago, Paula Bennett, previously ranked No 5, ended up being Acting Prime Minister for a day because John Key, Bill English, Gerry Brownlee and Steven Joyce were all out of the country. As Deputy Prime Minister, she will be acting PM a lot more regularly.
The tools English can use for promotion include: change in ranking, the portfolio itself, ministerial appointments outside and inside cabinet, officers of Parliament positions, appointment of whips, and select committee chairs.
Being made an Associate Minister can also signal a future promotion.
One of the biggest promotions in English's reshuffle is expected to be Associate Education Minister Nikki Kaye who is currently ranked 16 out of a cabinet of 20 and could make the new top 10 as Education Minister.
The only question is when, however. She has declared herself fit for work after treatment for breast cancer - and attended the caucus vote to replace John Key - but colleagues are concerned she wants to return to work too early.
2. Gerry Brownlee
Gerry Brownlee has been Number 3 in the Govt since 2006 when John Key became National Party leader, a position he kept in the past eight years of Government.
Brownlee had been deputy to Don Brash and willingly stepped aside for Bill English to become Key's deputy. He has kept the spot ever since. That will change today when Paula Bennett moves from No 5 to No 2 as the new deputy, and Steven Joyce, the new Finance Minister, moves from No 4 to No 3.
Brownlee will fall further down the list to let the new political generation rise, but he will still be part of the inner sanctum of the English kitchen cabinet, the informal group that runs the Government.
Housing presents Bill English with one of the most difficult dilemmas in his reshuffle because it has been a big problem area for this Government in both the public and private sectors. This term it has been divided into three portfolios under three different ministers: Social housing under Paula Bennett; Housing NZ under English himself; and Building and Housing with Nick Smith.
Political management has been a greater problem which is all the more damning because two of the players, English and Bennett, are so senior.
It has been slow to get going but significant work is now underway in each of the three which could benefit from continuity. For reasons of optics it may be tempting to give the whole lot to a new minister, but with housing being such a vital issue to the NZ economy and the Government's reputation, English won't want to take too many risks.
Gender balance is less important to National than Labour, but it is still a consideration, not so much with the senior cabinet positions which are usually entirely on merit, but in the ministry as a whole.
It is easier for a competent woman to get advancement than a competent male because there are fewer of them.
In John Key's cabinet of 20, seven were women, three of them being in the top 10 (Paula Bennett, Amy Adams and Hekia Parata).
Of the five ministers outside cabinet, three were women.
Geographic considerations are given no weighting in senior selections but in Key's top 10, four were from Auckland, three from Wellington, two from Christchurch and one from Tauranga.
While ethnicity plays no part in the senior cabinet appointments, Key had three ministers of Maori descent in his top 10: Paula Bennett, Simon Bridges and Hekia Parata.
5. Generational change
Real age doesn't matter in politics. It the year an MP was elected that matters more. Rarely is an MP promoted without serving an apprenticeship.
That means the impatient class of 2014 will probably have to breathe through their noses a bit longer to have their talents recognised in promotions.
Steven Joyce in National and Margaret Wilson in Labour are the two notable exceptions to the rule. Joyce was elected in 2008 and immediately became one of National's most powerful ministers. Margaret Wilson was elected in 1999 and became Attorney General.
Hekia Parata was promoted after being in Parliament for just two years, following the resignation of Pansy Wong.
Equally it is also unusual for an MP to be promoted after long apprenticeship if his or her party has been in Government for as long as eight years, although there are more exceptions in this category.