But a theory is not like an airline or bus timetable. We are not interested simply in the accuracy of its predictions. A theory also serves as a base… - Ronald Coase

A firm consist of the system of relationships which comes into existence when the direction of resources is dependent on an entrepreneur.

The question always is, will it pay to bring an extra exchange transaction under the organizing authority? At the margin, the costs of organizing within the firm will be equal either to the costs of organizing in another firm or to the costs involved in leaving the transaction to be “organised” by the price mechanism. Business men will be constantly experimenting, controlling more or less, and in this way equilibrium will be maintained. This gives the position of equilibrium for static analysis.

Outside the firm, price movements direct production, which is co-ordinated through a series of exchange transactions on the market. Within a firm, these market transactions are eliminated and in place of the complicated market structure with exchange transactions is substituted the entrepreneur-coordinator, who directs production. It is clear that these are alternative methods of coordinating production. Yet, having regard to the fact that, if production is regulated by price movements, production could be carried on without any organization at all might we ask, why is there any organization?