Gerry Adams will outline a timetable for his departure as leader of Sinn Féin on Saturday.
Some 3,000 party members are attending the party's conference, which began Friday in Dublin.
Motions on the party's position on abortion will be debated Saturday evening.
Having led Sinn Féin for 34 years, Mr Adams will tonight outline his plans for his eventual departure.
He is expected to run unopposed for the presidency of the party today, but will set the scene for who will replace him as leader at 8:30pm.
Mr Adams has said he wants party members to hear of his plans first, so no advance notice has been given of his speech, but deputy leader Mary Lou McDonald has long been tipped as the natural successor.
Speaking last night, she alluded to the change to come.
"The theme of generational change is very much part of the dynamic of this Ard Fheis.
"And as you know, Gerry Adams - over the course of this weekend - will set out his plans for the future".
This evening the party will hear debate on repealing the 8th Amendment of the Constitution - but is expected to maintain its position that members cannot vote according to their conscience, but rather must follow the party line.