Performance measurement remains a complex issue. This is particularly so if some absolute measure of performance is sought. A definition of performance in terms of value is restated and further developed. Reacting to this strict definition, the systems audit approach to measuring performance is developed and its use illustrated. Concludes that the absolute definition of maintenance performance, in terms of changes in value, presents difficult practical problems. Notes that a systems audit approach to performance measurement can potentially overcome some of these problems while preserving the focus on both business outcomes.