of type "Challenger" that is a heavy UK main battle tank). An object must have the capability to perform a function or to achieve an end. Thus, a description of capability is needed to give meaning to the value of objects in the sphere of operations. It should be possible to assign a location to any item in the sphere of operations. In addition, various geometric shapes need to be represented in order to allow commanders to plan, direct, and monitor operations. Examples include boundaries, corridors, restricted areas, minefields, and any other control measures needed by commanders and their staffs. Several aspects of status of items need to be maintained. The model must permit a description of the composition of a type object in terms of other type objects. Such concepts include tables of organizations, equipment, or personnel. The model must reflect information about what is held, owned or possessed in terms of types by a specific object item. There is a need to record relationships between pairs of items. Key among these is the specification of unit task organizations and orders of battle. The model must support the specification of current, past, and future role of objects as part of plans, orders, and events. The same data structure should be used to record information for all objects, regardless of their hostility status. Provision must be made for the identification of sources of information, the effective and reporting times, and an indication of the validity of the data." JC3IEDM development history and current maturity JC3IEDM has been developed from the initial Generic Hub (GH) Data Model, which changed its name to Land C2 Information Exchange Data Model (LC2IEDM) in 1999. Development of the model continued in a Joint context and in November 2003 the C2 Information Exchange Data Model (C2IEDM) Edition 6.1 was released. Additional development to this model, incorporating the NATO Corporate Reference model, resulted in the model changing its name again to JC3IEDM with JC3IEDM Ed 0.5 being issued in December 2004. Subsequent releases have seen areas of the model developed in greater depth than others and there is variation in the number of sub-types and attributes for each type in the current version. An example is HARBOUR within the FACILITY type which has 43 attributes compared to a VESSEL-TYPE with 12 attributes or a WEAPON-TYPE with 4 attributes. The associated attributes of a certain type also lack