The Office of the Prime Minister and Privy Council building, formerly known as the Langevin Block, is an office building facing Parliament Hill in Ottawa, Ontario, Canada. As the home of the Privy Council Office and Office of the Prime Minister, it is the working headquarters of the executive branch of the Canadian government.
The term Langevin Block was previously used as a metonym for the Prime Minister's Office and the Privy Council Office. The building was named after Father of Confederation and cabinet minister Hector Langevin. On June 21, 2017, Prime Minister Justin Trudeau renamed the building due to objections by Indigenous people of the name's use, due to Hector Langevin's role in establishing the residential school system, associated with the abuse of Indigenous children and attempts to forcibly assimilate them.
The building is a National Historic Site of Canada.