Consideration in English law

Consideration in English law is one of the four main building blocks of a contract. Consideration can be anything of value (such as an item or service), which each party to a legally binding contract must agree to exchange if the contract is to be valid. If only one party offers consideration, the agreement is not legally a binding contract. In its traditional form, expressed as the requirement that in order for parties to be able to enforce a promise, they must have given something for it (quid pro quo): something must be given or promised in exchange or return for the promise. A contract must be "met with" or "supported by" consideration to be enforceable; also, only a person who has provided consideration can enforce a contract. In other words, if an arrangement consists of a promise which is not supported by consideration, then the arrangement is not a legally enforceable contract. Mutual promises constitute consideration for each other. ("I promise you that I will do X, in consideration for which you promise me that you will do Y").

In Australia, the bargain theory of consideration prevails, where the act or forbearance of one party or promise thereof is the price for which a promise is bought.

Consideration for a particular promise exists where some right, interest, profit or benefit accrues (or will accrue) to the promisor as a direct result of some forbearance, detriment, loss or responsibility that has been given, suffered or undertaken by the promisee. The consideration must be executory or executed, but not past.

Consideration is executory when a promise to do something in the future is given in exchange for another promise to be done in the future. Consideration is executed when a promise is actually executed, in exchange for another promise to be executed in the future. Consideration is past when a promise has been given or executed before and independently of the other promise. For example, I promised to take you to lunch, and then when we got there I said "you must pay, because I have given you the benefit of my company". This is past consideration and therefore NO consideration.

Consideration can be anything of value (such as an item or service), which each party to a legally binding contract must agree to exchange if the contract is to be valid. If only one party offers consideration, the agreement is not legally a binding contract. In its traditional form, consideration is expressed as the requirement that in order for parties to be able to enforce a promise, they must have given something for it (quid pro quo): something must be given or promised in exchange or return for the promise. A contract must be "met with" or "supported by" consideration to be enforceable; also, only a person who has provided consideration can enforce a contract. In other words, if an arrangement consists of a promise which is not supported by consideration, then the arrangement is not a legally enforceable contract. Mutual promises constitute consideration for each other. ("I promise you to do X, in consideration for which you promise me to do Y").

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Wikipedia