For example, recall that RTP, Inc., manufactures hydraulic cylinders. The first activity, cutting rods, cutes long rods into the correct lengths for the cylinders. Next the cut rods are welded to cut plates. The cutting-rod activity is value-added because (1) it causes a change of state__uncut rods become cut rods, (2) on prior activity was supposed to create this change of state, and (3) it enables the welding activity to be performed. Though the value-added properties are easy to see for an operational activity like cutting rods, what about a more general activity like supervising production workers? A managerial activity is specifically designed to manage other value-added activities__to ensure that they are performed on an efficient and timely manner. Supervision certainly satisfies the anabling condition. Is there a change in state? There are two ways of answering in the affirmative. First, supervising can be viewd as an enabling resource that is consumed by the operational activities that do produce a change of state. Thus, supervising is a secondary activity that serves as an input that is needed to help bring about the change of state experted for value-added primary activities. Second, it could be argued that the supervision brings order by changing the state from uncoordinated activities to coordinated activities. Once value-added activities are identified, we can define value-added costs. Value-added costs are the costs to perform value-added activities with perfect efficiency.