A Virtual Acoustic Prototype (VAP) is a way of listening to a not-yet-existing machine in operation. It involves measurements and/or modelling of machine components which are then combined in the computer to produce a realistic sound of the full working machine. VAPs have been generated at Salford for various domestic products including washing machines and fan units, lawnmowers and automotive steering systems. Correct treatment of structure-borne sound is the speciality of the Salford team, headed by Prof. Andy Moorhouse. The methodology is general and can be applied to more or less any type of machine to predict the product sound, and even to rain noise on metal roofs. There is broad scope for research to develop VAPs of many more types of machines and products.