The Civil Contingencies Secretariat (CCS), created in July 2001 and disbanded in July 2022, was the executive department of the British Cabinet Office responsible for emergency planning in the United Kingdom. The role of the secretariat was to ensure the UK's resilience against disruptive challenge, and to do this by working with others to anticipate, assess, prevent, prepare, respond and recover. Until its creation in 2001, emergency planning in Britain was the responsibility of the Home Office. The CCS also supported the Civil Contingencies Committee, commonly known as COBRA.

In the aftermath of the Y2K bug scare, the fuel protests of 2000, flooding in autumn 2000, and the foot and mouth epidemic of 2001 the UK government felt that the existing emergency management policies and structures were inadequate to deal with natural or man-made disasters, and formed the Civil Contingencies Secretariat in July 2001, located in the Cabinet Office. Soon after the 9/11 attacks the remit of the CCS was expanded to include mitigating the consequences of a large scale terrorist attack.

Until 2001 the Home Office carried out emergency preparedness planning through its Emergency Planning Division, which in turn replaced the Home Defence and Emergency Services Division. From 1935 to 1971 a separate department, called the Civil Defence Department (in the early years the Air Raid Precautions Department, Ministry of Home Security), existed.

In 2002 David Blunkett, then Home Secretary, stated, in a written reply to a parliamentary question:

The remit of the Civil Contingencies Secretariat is to make the United Kingdom more effective in planning for, dealing with, and learning lessons from emergencies and disasters.

— David Blunkett,

He went on to state:

The Secretariat services the Civil Contingencies Committee, which I chair and in addition as part of the Cabinet Office reports to my right hon. Friend, the Prime Minister (Mr. Blair) through the Cabinet Secretary (Sir Richard Wilson).