The Home Office is the government department that primarily deals with affairs of security and public order.
At the moment the Home Office is undergoing some fairly radical reforms (it has been described as "not fit for purpose" in its present form) due to the fact that it is a somewhat cumbersome department whose remit is, some say, too much for one department.
Because it has to cope with internal law and order, the prison service, immigration and now an apparently growing terrorist threat, the Home Office has become something of a poisoned chalice for up-and-coming ministers.
The department has been the source of much controversy in recent times, with a number of high-profile prison and immigration scandals damaging the credibility of more than one Home Secretary - the present incumbent, Dr John Reid, is the third man to lead the Home Office in as many years.
It has been proposed that the department be split into two, an office of justice and one for security, although this is only a proposal for now.
Since the events of September 11th, one of the Home Office's key roles has been to protect the country from terrorist attack and, in the intervening years, it has passed a raft of controversial legislation aimed at achieving this. These new laws have caused much bad feeling among the Muslim community, who have complained of victimisation.