The three party leaders in the new Government will have to develop trust between each other immediately to avoid problems 'rippling out very fast' to other ministers and TDs, according to former Taoiseach Bertie Ahern.
Mr Ahern has suggested it's vital that Micheál Martin, Leo Varadkar and Eamon Ryan set an example.
Speaking on The Pat Kenny Show, he said: "From day one, trust will have to be developed between the three leaders - because if it doesn't come from the three leaders, then that ripples very fast to the rest of the table.
"[There can be] no surprises from the parties; no political gamesmanship... if people start playing games in constituencies, then that always gives bad feeling.
"The party advisors have to meet, they have to be clear on what's going forward... it's bad idea leaving obvious disagreements to the Cabinet table. Your political advisors have to be smart, have to be up for it - that they see potential pitfalls before they hit the Cabinet."
He suggested the goal among modern politicians is always to keep a Government intact for as long to a full Dáil term as possible, and that he believes people "will be trying" to keep the coalition going until 2024.
Mr Ahern said some of the Cabinet appointments were not expected - including the lack of a senior ministerial role for Fianna Fáil deputy leader Dara Calleary.
However, he suggested: "Picking the Cabinet, trying to get gender balance, trying to get regional spread is difficult... when it's three parties it's more difficult.
"The mistake, if it was a mistake that was made, was not plotting all 15 [ministers] on the map."
The former Taoiseach said he wasn't surprised by the appointment of Stephen Donnelly as Health Minister, as he'd been in that brief as opposition spokesperson.
He said: "There wasn't an obvious person that I could see that could take over Health.
"Normally a minister got maybe three-six months of having a run in... with Health that opportunity doesn't exist. Stephen is going to have to be on the frontline from day one."
Mr Ahern said he was surprised by the appointment of Norma Foley as Education Minister.
However, he noted that he's known her for a "long, long time" due to her involvement in local politics in Kerry, and that she's a "very able" school teacher so should perform well in the brief.