The theory of ethical economy analyses the ethical presuppositions of the market economy. It demonstrates that ethics is the pre-coordination in the motives of the economic agents anteceding the coordination of the price system in the market process. Ethical economy develops a positive theory of economic, ethical, and religious coordination of self-interested action described as a super-assurance game of prisoners' dilemma situations. It conceptualises ethics as the corrective of market failure and religion as the corrective of ethics failure. The formal ethics of coordination is then complemented by a theory of the material-substantive ethics of value qualities. One principle of ethical economy is the classical principle of double effect that is used for a theory of managerial and general decision-making. Unintended side-effects (externalities) are a central problem of decisions of large impact. Management decision making must exploit the potential for positive side-effects and control the negative side-effects of managerial decisions. The theory of ethical economy analyses the principles of just price and fair pricing and the relevance of the theory of just price for the pricing behaviour of the modern firm. Principles of Ethical Economy forms a theoretical synthesis of the market theory of modern economics and of the natural right tradition of ethics. It creates new insights into the ethics of the market as well as in the economics presuppositions and consequences of ethical duties, virtues, and goods.