PJHQ - The PJHQ's primary function is the planning and execution of joint, potentially joint and UK-led multinational operations. The PJHQ also has embedded within it a dedicated Command Secretariat, which provides policy, legal, presentation and financial advice to CJO during an operation.
Through this close relationship between civilian and military personnel, PJHQ is able to give politically aware military advice to the MOD.
Joint Commander - CJO will normally be appointed as the Joint Commander, although CDS may appoint one of the operational Commanders-in-Chief to act as a more senior Joint Commander if the operation is of a Large Scale.
In this case, CJO will act as the Deputy Joint commander whilst still retaining the mantle of Joint Commander for other operations.
Single-Service advice - The PJHQ has a number of dedicated single-Service appointments that work closely with their respective single-Service Operational Command HQs and have ready access to key members of staff and the single-Service deputies when required. This complements the advice given by MOD Directorates and allows full single-Service advice to be woven into coherent joint advice before submission to MOD Central Staff. Thus CDS and Ministers are provided with a fully balanced assessment on all aspects of a joint operation.
Supporting Commands - The 3 single-Service CINCs are responsible for providing forces for joint and multinational operations. These forces will be made available to CJO through the Joint Rapid Reaction Force which was established as a result of the 1998 Strategic Defence Review.