The project is in three phases

1.5  In the first phase, Modus provided services at Main Building, the Old War Office and two other central London buildings, Metropole Building and Northumberland House, while the latter three, and another building, St Giles Court, were prepared for the decant of staff from Main Building. The scale of redevelopment work meant that it was necessary for staff to decant to alternative accommodation while work was under way. In the second, the decant phase, Modus is continuing to provide services at the four decant buildings, while it redevelops Main Building. In the third phase, after the redevelopment of Main Building, it will be responsible, for some 25 years, for the provision and upkeep of that building and the Old War Office. The unitary charge payable increases after the reoccupation of Main Building. The project also relies on other management arrangements. MOD is responsible for the provision of IT systems in the decant buildings and in Main Building when it is reoccupied. Telephone services are provided under MOD's Defence Fixed Telecommunications Services PFI contract with BT.

1.6  MOD will reduce Head Office staff numbers in London by 30 per cent from 6,020 at 1 April 1999 to 4,300 after redevelopment of Main Building as shown in Figure 3.