McNie to be installed as Moderator
Up to 1,000 people are expected to attend the General Assembly of the Presbyterian Church.
The three-day event opens in Belfast tonight with the formal election and public installation of the church's new moderator Dr Ian McNie.
The 64-year-old father of two from Trinity Presbyterian Church in Ballymoney, Co Antrim was nominated by 12 of the 19 presbyteries in February.
Dr McNie, who describes himself as a "conservative evangelical" will be the 176th Moderator since the election of Dr Samuel Hanna in 1840.
He takes over from outgoing Moderator, Reverend Michael Barry.
More than 600 clergy and 100 civic guests are expected to be among the delegates at the church's city centre headquarters over the next few days.
Votes will be cast on more than 80 resolutions.
Clerk of the General Assembly and General Secretary of the church, Rev Trevor Gribben said he expected a busy but productive series of engagements.
He said: "Democracy is one of the strengths and hallmarks of Presbyterianism and the General Assembly is where decisions are taken, the significant, the routine and the mundane together, that can affect the direction the church takes for years to come, with the vast majority of our business conducted in public who are very welcome to attend."
The installation and public sessions of the General Assembly will be streamed online or can be followed on Twitter via the hashtag #PCIGA15.