A situation in which the market does not allocate resources efficiently. Market failure can occur for one of three reasons. It may occur when one party has power that can prevent efficient transactions from occurring. An example is a monopoly. A second reason is the possibility that an efficient transaction can have externalities (side effects) that reduce efficiency elsewhere in the market or the broader economy. Finally, market failure can occur because of the nature of certain goods or services. Some analysts believe that market failure is usually the result of insufficient government protection of property rights. Market failure has been cited as a reason for government intervention in the economy. See also: Government failure.