Closely related to the concept of consideration is the mutuality of obligation doctrine. Under this doctrine, both parties must be bound to perform their obligations or the law will treat the agreement as if neither party is bound to perform. When an offeree and offeror exchange promises to perform, one party may not be given the absolute and unlimited right to cancel the contract. Such arrangements attempt to allow one party to perform at her leisure, while ostensibly not relieving the other party of his obligations to perform. Most courts declare these one-side arrangements null for lack of mutuality of obligation. Some courts simply invalidate such contracts for lack of consideration, reasoning that a party who is given absolute power to cancel a contract suffers no legal detriment.
To avoid having a contract subsequently invalidated by a court, the parties must be careful to limit their discretion to cancel the contract or otherwise not perform. As long as the right to avoid performance is dependent on some condition or event outside the control of the party seeking to cancel the contract, courts will find that mutuality of obligation exists. Thus, a farmer might lawfully be given the right to cancel a crop-watering service if the right to cancel were conditioned upon the amount of rain that fell during a given season, something outside the farmer’s control. But a court would find mutuality lacking if the farmer were given the right to terminate the service short of full performance simply by giving notice of his or her intention to cancel.