This trilogy deals with an epistemology of economics, arguing for a radical overturning of conventional analysis and providing an alternative to political economy and social sciences, based not on positivism, but on a normative and programming paradigm. Volume III furthers and concludes work presented in Volume I and Volume II, and introduces a concrete and practical example of how to build a Planning Accounting Framework (PAF), as associated with Frischs plan-frame (explored in Volume II), to demonstrate the extent to which decisions and negotiations can be routed in the social sciences. The PAF is an instrument of the programming approach that can be used to verify the compatibility of decisions and their effects. The author builds on Frischs classical PAF to maximise the phenomenology of economic systems, and assure a consistent and effective implementation of decision making.