Each party to a contract must provide something of value that induces the other to enter the agreement. The law calls this exchange of values “consideration.” The value exchanged need not consist of currency. Instead, it may consist of a promise to perform an act that one is not legally required to do or a promise to refrain from an act that one is legally entitled to do. For example, if a rich uncle promises to give his nephew a new sports car if he refrains from smoking cigarettes and drinking alcohol for five years, the law deems both the uncle’s promise and the nephew’s forbearance lawful consideration.
A court’s analysis as to whether a contract is supported by sufficient consideration typically focuses more on the promise or performance of the offeree than the promise or performance of the offeror. Courts often say that no consideration will be found unless the offeree suffers a “legal detriment” in making the return promise or in performing the act requested by the offeror. As a general rule, legal detriment is found if the offeree relinquishes a legal right in fulfilling his or her contractual duties. Thus, promises to give love and affection or make a gift or donation are not sufficient consideration to support a contract because no one is under a legal duty to give or refrain from giving these things to others. Similarly a promise to perform an act that has already been completed in the past fails to offer consideration to support a new agreement.