Deputies from the Green Party, Sinn Féin, the Socialist Party and Independents have formed a technical group to maximise their input into Dáil proceedings.
Stressing this is a tactical rather than an ideological arrangement, the group expects to have 22 members, giving them extra rights to question the Taoiseach and Ministers on issues of current controversy.
This will give them a higher profile in the Dáil and - most importantly for them - greater media publicity.
The group will be the third largest in the Dáil, behind Fianna Fáil and Fine Gael.
The development means they will be called to ask questions of the Taoiseach and Ministers before the Labour Party, which has 21 deputies.
The formation of the group follows months of negotiation with the main political parties, during which they sought extra rights to reflect the changed composition of the Dáil.
Both the Green Party and Sinn Féin were short of the seven deputies required to form a party grouping in the Dáil.
The technical group's members will rotate the right to ask questions and to speak.