Cabinet Office Briefing Room (COBR) is a term used to describe the formation of a crisis response committee, co-ordinating the actions of bodies within the government of the United Kingdom in response to instances of national or regional crisis, or during events abroad with major implications for the UK. The constitution of a COBR will depend on the nature of the incident but it is usually chaired by the Prime Minister or another senior minister, with other key ministers as appropriate, and representatives of relevant external organisations such as the Association of Chief Police Officers and the Local Government Association.

What does Cobra do?

Often labelled an emergency council, Cobra meets to discuss high-priority issues that cross departmental borders within government. In the case of a strike by fire crews, the government will have to co-ordinate a response from the army and other emergency services.

So why the funky name?

It is often incorrectly referred to as COBRA or Cobra by the media, this is thought to relate to the acronym for Cabinet Office Briefing Room A as the meetings were usually held in Conference Room A at the Cabinet Office main building at 70 Whitehall, this abbreviation is no longer used within the Cabinet Office. Cobra stands for Cabinet Office briefing room A. Cobra meetings are held in Downing Street, within Cabinet Office buildings. In most cases Cobra is convened as part of the civil contingencies committee, which plans government responses in times of emergency.

Who's on the board?

The make-up of the Cobra committee depends entirely on the nature of the issue, as the name refers to the location of the meeting, not a particular set of people.

How often does Cobra meet?

It has met four times during Mr Blair's tenure. It was first called to combat the fuel strikes in November 2000, later the foot and mouth outbreak the following spring and then after the September 11 attacks. In March this year the prime minister convened it to deal with the street crime initiative.

Is this an emergency measure?

The government today denied this. It cited the fact the committee met to deal with the street crime initiative as proof it was not a panic measure. However, today's meeting is under the auspices of the civil contingencies committee, whose official remit is "to co-ordinate the preparation of plans for ensuring in an emergency the supplies and services essential to the life of the community; to keep these plans under regular review; to supervise their prompt and effective implementation in specific emergencies; and to report as necessary to the appropriate ministerial committee." It is clear the group only convenes to tackle extremely high-priority or potentially disruptive issues and is a sure sign the government is taking the strike very seriously indeed.

What kind of measures will it authorise?

It will co-ordinate the role of government agencies in responding to the strike by fire-fighters. As a priority it will deal with the deployment of army-staffed Green Goddess fire engines. In addition, it will consider the problems posed if, as threatened, rail workers join firemen in industrial action.