The market price system contributes to economic efficiency. First of all, producers are driven by the profit motive to produce things which consumers want. And markets clear at equilibrium prices that are acceptable to buyers and sellers. However, public policy makers may decide that the market does not adequately reflect some relevant aspects of demand or supply,
such as benefits from public transportation or the "social" costs of pollution. The government may then attempt to improve resource allocation by embracing a broader perspective, and spending to support public transportation and taxing to discourage pollution.
Efficiency is also promoted because producers respond to prices by comparing them to their costs of production. The level of production will tend to be driven by comparing incremental (marginal) production costs with price. Producers will tend to increase production as long as price exceeds incremental costs. Profit would then be determined by any difference between total revenue and total cost.
Those firms using the best management and production methods will be the most successful, and will be emulated. Competition will tend to drive inefficient firms out of business. In the "short run" the firm's output is limited by having at least one fixed factor of production, such as its factory size. In the "long run" the firm has enough time to add to or reduce its capacity in response to the marketplace, which includes cost, price, and profit signals.
Planners for national emergencies must be aware of the nature of the market price system, and the difficulties in ignoring or attempting to control prices. Also, the way in which firms respond to price incentives must be considered in any attempt to influence output for national emergency purposes.
如从福利的公共交通，或“社会”的成本污染。政府可能然后尝试，以改善资源分配，由接受更广泛的角度，和开支，以支持公共交通和征税，以阻止污染。
效率也促进了生产者的回应，因为价格比较，让他们的生产成本。生产水平将趋于驱动比较增量（边际）的生产成本与价格。生产者往往会增加生产，只要价格超过增量成本。利润，然后将取决于任何差别的总收入和总成本。
这些公司使用最好的管理和生产方法，将成为最成功的，并会仿效。竞争将趋于驱动器效率低，公司出于业务。在“短期而言， ”该公司的产量是有限的，由至少有一个固定的生产要素，如它的厂房面积。在“长远来说， ”该公司有足够的时间来加入或减少其能力在回应市场，其中包括成本，价格和利润信号。
规划为国家紧急情况必须意识到的性质，市场的价格体系，和困难，在无视或试图控制价格。此外，以何种方式公司回应价格诱因，必须考虑在任何试图影响输出国家紧急用途。
