The theory of the firm consists of a number of economic theories that explain and predict the nature of the firm, company, or corporation, including its existence, behavior, structure, and relationship to the market.
In simplified terms, the theory of the firm aims to answer these questions:
Firms exist as an alternative system to the market-price mechanism when it is more efficient to produce in a non-market environment. For example, in a labor market, it might be very difficult or costly for firms or organizations to engage in production when they have to hire and fire their workers depending on demand/supply conditions. It might also be costly for employees to shift companies every day looking for better alternatives. Similarly, it may be costly for companies to find new suppliers daily. Thus, firms engage in a long-term contract with their employees or a long-term contract with suppliers to minimize the cost or maximize the value of property rights.
The First World War period saw change of emphasis in economic theory away from industry-level analysis which mainly included analyzing markets to analysis at the level of the firm, as it became increasingly clear that perfect competition was no longer an adequate model of how firms behaved. Economic theory until then had focused on trying to understand markets alone and there had been little study on understanding why firms or organisations exist. Markets are guided by prices and quality as illustrated by vegetable markets where a buyer is free to switch sellers in an exchange.
The need for a revised theory of the firm was emphasized by empirical studies by Adolf Berle and Gardiner Means, who made it clear that ownership of a typical American corporation is spread over a wide number of shareholders, leaving control in the hands of managers who own very little equity themselves. R. L. Hall and Charles J. Hitch found that executives made decisions by rule of thumb rather than in the marginalist way.