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This case (Hughes v Metropolitan Rly Company (1877) 2 AC 439), although intersting in its own right, is most famous for being used to support the decision in High Trees House case (see: Central london property trust ltd v high trees ltd (1947)).

A landlord was entitled, under the terms of a lease, to compel a leaseholder to carry out repairs to the property, given an adequate period of notice. The landlord gave a six month notice period but, during this time the landlord and leaseholder entered into negotiations over the sale of the land. The leaseholder was given to understand that the repairs need not be carried out if he was going to purchase the land. When the negotiations broke down, the landlord attempted to enforce the original six-month period and evict the tenant. The court ruled that the negotions over the sale constituted a promise not to enforce the repair order, and that the tenant had acted on that promise to his detriment. The principle of Promissory estoppel could therefore be used to estop the landlord enforcing his strict rights. In this case the suspension of the landlords strict rights were merely suspended, and a new notice period introduced. The most controversial part of the High Trees judgement was that the promisor was prevented indefinitely from claiming his strict rights.