This article or section deals primarily with the United States and does not present a worldwide view of the subject.

Continuity of Government (COG) is the principle of establishing defined procedures that allow a government to continue its essential operations in case of a nuclear war or other catastrophic event. Developed during the Cold War, COG plans were implemented by many countries to avoid leaving a vacuum at any governmental level, which could lead to anarchy or to an unlawful assumption of authority. Effectively the democratic process is revoked temporarily until the effects of the event have subsided and normal government can resume. It is not a generally published part of government policy and is generally shrouded in secrecy for security reasons.

Continuity of Government in the United States
The main points of such a plan in the United States are to suspend certain parts of the United States Constitution and to allow the alternative use of federal land and buildings (including use as internment camps) by FEMA for the housing/detention of US citizens as required, as well as any rescue/recovery operations. It also allows for power in the US to be centralized to the White House and "appointment of military commanders to run state and local governments and declaration of martial law". In the former regard the United States arrangements for Continuity of Government are unusual. The plans in most countries are intended to preserve the legal and constitutional framework, the American system relies on circumventing it. There is no legal basis for the imposition of so-called "martial law".

House Democrat Jack Brooks brought up the issue during the Iran-Contra Affair hearings. Try as he might, he was not able to get the answers to his questions from Col. Oliver North, (it had been reported in the Miami Herald that North had worked on such plans) as he was repeatedly requested by the Chairman to refrain from discussing the issue and to request for a (non-public) executive session if he wanted to discuss the issue at all.

Apparently the Legislative and Judiciary Branches pf the US Government each have similar continuity plans. However, both require the Executive to notify them before they are activated. There appears to have been no notification following 9-11 to either the Congress or US Supreme Court until it was finally admitted to Congress in 2002.