The Assembly Rooms is a Grade B1 listed building in Belfast, Northern Ireland. It was built, as the single-storey Exchange, in 1769 by Arthur Chichester, 1st Marquess of Donegall. The Marquess expanded to a second floor in 1776 and the building came to be known by its current name. It housed the Belfast Harp Festival of 1792, public meetings and, following the Irish Rebellion of 1798, the court martial of rebel leaders.