The authors propose a quality model as a framework which should facilitate the evolution of theoretically based systems of measurement for the processes and products of the software development lifecycle. They start by defining measurement and quality measurement, and they present a model for software quality measurement. This model is used to explore several fundamental concepts and as a framework for the development of a set of software quality metrics. The authors discuss how the model can be developed through experimental work and by developing current and potential applications of the model in its immature state. These include process optimization, quality specification, end product quality control, intermediate product quality control, and the prediction of software quality. The authors conclude with a discussion of current issues and future trends in this area. Topics covered include education, the evolution of standards for data definition, and tool support.>