This book challenges the mainstream paradigm with the introduction of a new methodology. Economies are represented realistically in a fully articulated system of national income and flow of funds accounts. The authors study how flows of income, expenditure and production are intertwined with stocks of assets and liabilities, determining how whole economies evolve through time. Starting with extremely simple stock-flow consistent models, the text describes a succession of increasingly complex models constructed with such rigor that, in harmony with its basis in accounting, there is always one equation which is implied logically by all the others. Readers will be able to download all the models and explore their properties for themselves.