Promissory estoppel protects an individual from loss suffered as a result of being induced by the representor to believe that certain contractual rights will not be enforced.
Promissory estoppel has developed significantly over the years. In the case of Central London Property Trust v High Trees House Ltd there was a revival and broadening of the principle. It was stated that in situations of a pre-existing contract where a representor makes any representation affecting legal relations, and that representation was (and was intended to be) acted upon, promissory estoppel will prevent the representor from acting inconsistently with that representation. In the subsequent case of Waltons Stores (Interstate) Ltd v Maher, it was clarified that promissory estoppel can arise in pre-contractual negotiations, and can be used to support a case of action in contract. This was a landmark decision, signalling a departure from the previously accepted understanding that consideration was required.