With a plethora of models, systems and standards to choose for a basis of software process improvement, decisions on which to adopt may depend on a number of factors. This paper presents an evolutionary and extremely cost effective approach to implementing a software quality system that requires minimum resource and little disruption to programme delivery. The method presented, achieved a 40% improvement in the level of implementation of the AWE plc software quality management system over a 5-year period. A critical success factor is the treatment of the users’ of the defined software quality system as customers, understanding their concerns and problems, and being responsive to them. The importance of a well designed system is highlighted together with the essential and extensive consultation process required to gain buy-in and lay the foundation for cultural change. This was supported with a helpful programme of facilitated self-assessment and sustained by a closely aligned training scheme. As a consequence some of the cultural elements were changed from one of thoughtless “tick-in-the-box” compliance to one of true understanding of the system requirements, true quality implementation, and subsequent added value.