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Allocative inefficiency - Allocative efficiency theory says that the distribution of resources between alternatives does not fit with consumer taste (perceptions of costs and benefits). For example, a company may have the lowest costs in "productive" terms, but the result may be inefficient in allocative terms because the "true" or social cost exceeds the price that consumers are willing to pay for an extra unit of the product. This is true, for example, if the firm produces pollution (see also external cost). Consumers would prefer that the firm and its competitors produce less of the product and charge a higher price, to internalize the external cost.

Distributive Inefficiency - refers to the inefficient distribution of income and wealth within a soceity. Decreasing marginal utilities of wealth suggests that more egalitarian distributions of wealth are more efficient than unegalitarian distributions. Distributive inefficiency is often associated with economic inequality.

Economic inefficiency - refers to a situation where "we could be doing a better job," i.e., attaining our goals at lower cost. It is the opposite of economic efficiency. In the latter case, there is no way to do a better job, given the available resources and technology.

Keynesian inefficiency - might be defined as incomplete use of resources (labor, capital goods, natural resources, etc.) because of inadequate aggregate demand. We are not attaining potential output, while suffering from cyclical unemployment. We could do a better job if we applied deficit spending or expansive monetary policy.