Former minister Eamon Ryan is among three candidates vying for leadership of the Green Party who will learn their fate on Friday.
Councillor Malcolm Noonan and party activist Phil Kearney, a member of its National Executive Council, have also been put forward for the post.
A spokeswoman said the election of the new leader is seen as the first critical step in the Green Party's rebuilding after the general election in February.
The Greens suffered a hammering, losing all six of their Dail seats.
Party hustings have taken place around the country, with up to 50 members attending each one.
Former environment minister John Gormley announced his plans to step down as party leader in March.
Under the party's constitution, a leader's term in office runs for five years and it must hold a leadership contest within six months of a general election.
Mr Gormley, who became leader in July 2007 after taking over from Trevor Sargent, deputy leader Mary White and chairman Dan Boyle will be among the members at the announcement at the Green Party offices in Dublin on Friday.