The right of a party to a contract to deprive the other party, who has breached (broken) the contract, of a gain that he has unjustly made.
This method of assessing damages is used where:
• there has been a complete failure of consideration , and the party in breach has made a gain, e.g. a buyer has paid for goods in advance and has not received them;
• the party in breach has made an unjust gain, although the wronged party has not suffered any real loss.