This text presents a first course in microeconomics which is suitable for both MBA and upper level undergraduate programmes. No previous knowledge of economics is assumed. The text demonstrates how the interactions of producers and consumers in product markets produce powerful tendencies towards efficiency and equality when self-interest is harnessed within purely competitive markets, as well as how rent-seeking activity can alter this conclusion. The text finishes by showing how human-capital investments can increase the productivity and wages of workers. As economics is presented to students as an element in arguments, only the economics necessary to support the arguments need to be presented. This feature makes this book substantially leaner than the standard text in microeconomics, thereby making it potentially far more accessible.