Standard information representation in the manufacturing business has always focused on products with information relating to their design, geometry and required processes. However there is no standardized information model available to represent the manufacturing equipment used to produce such products. This equipment contributes as a significant investment in setting up a CNC manufacturing facility and is considered as a major asset of the business. Thus the authors see a need for an effective model to represent such equipment particularly the most expensive assets namely CNC machining systems. Such a model could represent the machine resource and also its additional auxiliary devices such as workpiece and cutting tool changing mechanisms, bar feeders, pallet/gantry systems and robotic arms. These devices can function with a CNC only when the controller's resource data model can represent their functionality. Currently every machine tool and auxiliary device manufacturer promotes their own resource data models; resulting in a plethora of representation methods which are bespoke and incomplete in terms of representing the entire system's resources. This paper proposes a Unified Manufacturing Resource Model termed UMRM. UMRM not only has the novel capability to provide the information to define the various elements of the CNC machining system, but also has the added capability to provide support for automation of process planning decision making. (C) 2009 Elsevier Ltd. All rights reserved.