In a unilateral contract, one party makes a promise in exchange for an action of the other party. Insurance policies are unilateral contracts. If you purchase liability insurance or any other type of policy, you pay a premium (a deed) in return for the insurer`s promise to pay future claims. If a party makes a statement or promise that prompts another party to rely on that statement in such a way that it is financially aggrieved by that reliability, a court will keep the statement or promise as if it were a contract. The court does not need to find an agreement or consideration to enforce the promise as a contract, but it is difficult to prove that a statement was made without registration. Most contracts are bilateral. This means that each party has made a promise to the other. When Jim signed the contract with Tom`s Tree Trimming, he promised to pay a certain amount of money to the contractor once the work was done. Tom, on the other hand, promised Jim to complete the work described in the agreement. In Eastwood v Kenyon, a girl`s caretaker has arranged a loan to educate the girl and improve her chances of marriage. After her wedding, her husband promised to repay the loan. It was found that the guardian failed to keep the promise, since the loan to raise and educate the girl was late because it was over before the husband promised to repay it.  A promise cannot be based on a reflection that was said, made or made before the promise.
Something that will be said later will not be considered a quid pro quo. For example, if X promises to reward Y for an act that Y has already accomplished, then the execution of that act is a good reflection, because the promise to be rewarded for it is a past reflection and therefore not a good reflection. A contract in which the parties exchange a promise for a promise is referred to as a bilateral treaty, while a contract in which one party makes a promise and the other party performs an act is characterized as a unilateral treaty. The idea of giving the cure to a person who has broken his promise is for most people. The « harmful » abandonment of the promise (the person to whom the promise is given) on the promise must, however, be reasonable and predictable by the Promisor (the person who made the promise) at the time of his statement. If the advertiser takes steps that the promiseor could not have expected, the Promisor is not bound to keep the promise. A promise can be implemented if it is supported by a quid pro quo, that is, where the reflection has deviated from the promise. In the case of Tweddle v Atkinson, john Tweddle William Guy, for example, promised that he would pay money to William Guy`s child, and William Guy also promised John Tweddle that he would pay money to John Tweddle`s child after the marriage of the two children.