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Although most contracts are discharged to the satisfaction all parties (see: Contract), particular difficulties arise when a contract is breached after partial completion (see: Breach of contract).

In general, a contract will only be discharged bu complete fulfilment of its terms. If the contract stipulates this explicitly then there is even stronger grounds for supposing so. Such a contract is often referred to as 'entire'. However, there are cases where partial performance does not constitute a breach.

• The court may deem that the contract is not entire, but of 'severable obligations'. A party that breaches the contract before being paid may be entitled to a quantum meruit award in respect of the work done.
• Even if the contract is inescapably entire, the court may rule that the contract has been 'substantially performed' if the breaching part carries out most of the obligation. In this case the party not in breach may only be awarded sufficient Damages to complete the work (e.g., see: Hoenig v isaacs (1952)).
• Acceptance of part performance. If one of the parties to the contract fulfils only part of his obligation, it is a defence to say that this breach was acceptable to the other party. Moreover, the acceptability may be signalled by conduct, rather than explicitly. In this case, the party in breach may apply for a Quantum meruit award for the work completed. However, this defence will not be upheld if it can be shown that the injured party had little choice but to continue as if he accepted the breach. For example, in Sumpter v Hedges a man who completed building work that had been left incomplete by another was deemed not to have accepted the breach, because he had little choice by to complete it himself (see: Sumpter v hedges (1898))