Pickering Real Estate Lawyer, England

A promise that pledges nothing, because it is vague or because the promisor can choose whether or not to honor it. Such promises are not legally binding. For example, if you get a new job and promise to work for three years, unless you resign sooner, you haven't made a valid contract and can resign or be fired at any time.

A legal doctrine that requires landlords to offer and maintain livable premises for their tenants. If a landlord fails to provide habitable housing, tenants in most states may legally withhold rent or take other measures, including hiring someone to fix the problem or moving out. See constructive eviction.

A business guest, or someone who enters property held open to members of the public, such as a visitor to a museum. Property owners must protect invitees from dangers on the property. In an example of the perversion of legalese, social guests that you invite into your home are called 'licensees.'

A provision in a deed or will that attempts to restrict ownership of the property -- for example, selling your house to your daughter with the provision that it never be sold to anyone outside the family. These provisions are generally unenforceable.

Principles of international law so fundamental that no nation may ignore them or attempt to contract out of them through treaties. For example, genocide and participating in a slave trade are thought to be jus cogens.

The building of a structure entirely or partly on a neighbor's property. Encroachment may occur due to faulty surveying or sheer obstreperousness on the part of the builder. Solutions range from paying the rightful property owner for the use of the property to the court-ordered removal of the structure.

A legal claim that one party failed to perform as required under a valid agreement with the other party. For example you might say, 'The roofer breached our contract by using substandard supplies when he repaired my roof.'