The National Nuclear Corporation (NNC), formerly Nuclear Power Company (NCP), was established in June 1973 to consolidate and strengthen the nucelar power station industry into a single unit. It was a nuclear power plant design and construction contractor. It often worked internationally, collaborating with Westinghouse in the US and constructing nuclear power stations in Japan and Italy.

It had two principle office and laboratory sites, at Risley, Cheshire and at Whestone, Leicester.