Presented here is a set of methods and tools developed to provide transportable measurements of performance in heterogeneous networks of machines operating together as a single virtual heterogeneous machine (VHM). The methods are work-based rather than time-based, and yield significant analytic information. A technique for normalizing the measure of useful work performed across a heterogeneous network is proposed and the reasons for using a normalized measure are explored. It is shown that work-based performance measures are better than time-based ones because they may be (1) taken while a task is currently executing on a machine; (2) taken without interrupting production operation of the machine network; (3) used to compare disparate tasks, and (4) used to perform second-order analysis of machine network operation. This set of performance tools has been used to monitor the utilization of high-performance computing networks, provide feedback on algorithm design and determine the veracity of computing performance models. © 1997 Taylor and Francis Group, LLC.