Industrial Organization is used as an analytical framework, to make relations amongst market structure, market conduct and market performance. It builds on the theory of the firm, a set of economic theories that describe, explain and attempt to predict the nature of a firm in terms of its existence, behavior, structure and its relationship to the market. Industrial Organization is a field of economics dealing with the strategic behavior of firms, regulatory policy, antitrust policy and market competition. It has also had significant practical impacts on antitrust law and competition policy.