The first person to take on a new responsibility after the decision of David Andrews to resign as Minister for Foreign Affairs will be the Taoiseach himself. Once the Dail is officially informed tomorrow of the resignation of Mr Andrews, Mr Ahern will temporarily add to his responsibilities by taking over the foreign affairs portfolio.
The President, Mrs McAleese, who will give the new ministers their seals of offices, is out of the State until Thursday. In her absence, the Taoiseach could go through the formalities with the Presidential Commission which deputises in such circumstances.
However, Mr Ahern is keen that the President be involved in the ceremonies - the first ministerial appointments since her election - so he will have the additional responsibilities at Iveagh House until Thursday evening.
Those close to the Taoiseach are advising a major reshuffle going beyond filling the one Cabinet vacancy created by the departure of Mr Andrews. However, the introduction of new faces at senior and junior ministerial level would involve asking people to stand aside. This is a task which Mr Ahern may be loath to undertake.
In these matters, his record has been marked by innate conservatism. After becoming leader of Fianna Fail in late 1994, Mr Ahern never reshuffled his opposition front beach. When he was elected Taoiseach in June 1997, he remained loyal to his senior colleagues.
Indeed, the Taoiseach may well conclude that this formula has been successful, as evidenced by the latest MRBI/Irish Times opinion poll. With the Government doing so well in the electorate's eyes, why take the risk of upsetting the personal, political and regional balance at minister and minister of State level?
The likelihood is for some limited movement of seats at the Cabinet table. Mr Brian Cowen remains the favourite for the foreign affairs job. However, should the reaction to the early public association of the Minister for Health with the position at Iveagh House be viewed as any way negative, Mr Ahern could turn to the Minister for Justice, Mr O'Donoghue, who is a close political associate.
There may also be the temptation to return Mr Cowen to an economic ministry. Under Mr Albert Reynolds, he served first as minister for labour and later as minister for transport, energy and communications.
Such a scenario could see Ms Mary O'Rourke come into the reckoning for foreign affairs, with the Mr Cowen taking over at the Department of Public Enterprise. However, if, as the strong money indicates, Mr Cowen does get foreign affairs, then John O'Donoghue and Mary O'Rourke will stay put, with the Minister for Education, Micheal Martin, moving sideways to Health.
Filling the one vacancy at Cabinet may then involve some musical chairs to ensure the promoted member receives one of the less-taxing ministerial positions. Who gets the promotion remains unclear.
In the past, the Taoiseach has placed emphasis on seniority and experience. That should benefit the Government Chief Whip, Mr Seamus Brennan. There was a great deal of surprise in political circles at his comments to a Sunday newspaper supporting his own case for advancement. Then there is his role with the four key independent TDs who have deals to support the Government.
Should Mr Brennan be overlooked, then several junior ministers can have the expectation of getting the nod from the Taoiseach. They include Mr Martin Cullen, Mr Willie O'Dea, Mr Frank Fahey, Mr Tom Kitt and Mr Chris Flood.
The fact that the south-east is not represented at the Cabinet table could help Mr Cullen's case. However, the same argument could also be made about Connacht and south Dublin where there are no senior Fianna Fail ministers.
If the reshuffle, in terms of opportunities for promotion, is limited to responding to the resignation of Mr Andrews, there will be many disappointed junior ministers. A similar feeling may also surround backbenchers such as Mr Eoin Ryan, Ms Mary Hanafin and Mr Brian Lenihan.
On seniority, Mr Ryan should be promoted. However, as one of his party colleagues observed yesterday in relation to all the reshuffle speculation, "Nobody knows what is going on in Bertie's mind".
All will be revealed on Thursday when after a Dail vote the President will receive the Taoiseach and his new appointees at Aras an Uachtarain. While ministers of State are selected by the Taoiseach, their formal appointment requires cabinet approval, so one of the first tasks of Mr Ahern's new ministerial team on Thursday is likely to be to approve these changes.