The group chief executive of Bank of Ireland and the former head of Ulster Bank will appear before the banking inquiry today.
Richie Boucher, who took over at the helm of BOI in the wake of the bank guarantee, and Cormac McCarthy are expected to be pressed about the impact the guarantee and the economic bailout had on their financial institutions.
The inquiry is currently in its Nexus phase. It is expected members of the committee will hear from the former Taoiseach Brian Cowen on a number of occasions this summer.
A final report from the group is expected by the end of November.