Landmark Contract cases

Courts won't assess adequacy of consideration, only legal sufficiency required

Court establishes right to sue immediately for anticipatory breach of contract

Performance exceeding contractual duty constitutes consideration if substantially more onerous.

Part payment of debt cannot discharge larger debt without fresh consideration

Tickets issued after payment cannot retrospectively introduce exclusion clauses without prior notice.

Hotel exclusion clauses in bedrooms cannot be incorporated into contracts made at reception.

House of Lords establishes 'radical change' test for frustration of contracts

Legal duty plus additional benefit can constitute valid consideration for contract formation.

Frustration requires fundamental change to contractual adventure, not mere inconvenience or expense.

Third party cannot sue on contract but representative capacity provides remedy

Separated spouses' agreements presumed legally binding unlike harmonious domestic arrangements

Face-to-face contracts are voidable for fraud, not void for identity mistake.

Promissory estoppel can found a cause of action in Australian law where unconscionable reliance occurs

Undue influence requires transaction shown to be manifestly disadvantageous to complainant

Mental distress damages require physical inconvenience and must be modest in amount.

Practical benefit can constitute good consideration for contract modification

Actual undue influence does not require manifest disadvantage or put banks on notice.

Williams v Roffey limited: does not apply to part payment of debts.

Mental distress damages available where peace of mind is important contractual object.

Written contracts naming a real person who never consented are void; face-to-face dealings create voidable contracts.

Domestic promises between spouses presumed to lack legal intent

Payment of lesser sum cannot discharge greater debt without fresh consideration.

Past consideration may be good consideration if requested act performed with expectation of payment

Contractual obligations are absolute; impossibility of performance provides no excuse without express provision.

Performing existing duties provides no consideration for new contractual promises

Court establishes postal rule: acceptance effective when letter posted

An offeror may withdraw an offer at any time before acceptance, even if they promised to keep it open.

Performance of existing legal duty cannot constitute consideration for a new promise.

No rescission for misrepresentation if party relied on independent verification.

Counter-offer kills original offer, preventing later acceptance of initial terms

Contractual damages should put innocent party in position as if contract performed.

A promise not to complain is not valid consideration for a contract

Court establishes landmark test for recoverable damages in contract breach

Anticipatory repudiation can be retracted if not accepted by the innocent party.

Contracts for sale of non-existent goods are void for common mistake.

Promise to pay nephew upon marriage constituted valid consideration for contract

Third parties cannot enforce contracts made for their benefit

Performing duty owed to third party constitutes valid consideration for new contracts.

Silence cannot constitute acceptance of contractual offer

Contract automatically discharged when performance becomes impossible through no fault of parties

Contract void when parties mean different things by same ambiguous term

Offers lapse after reasonable time; six months too long for shares.

Fiduciary duty arising from confidential relationship requires full disclosure in transactions

Threats of criminal prosecution constitute duress rendering contracts voidable

Entire contracts require complete performance before payment becomes due; no recovery for partial performance.

Advertisements for tenders are invitations to treat, not binding offers.

Court establishes objective test for contractual agreement over subjective intentions

An advertisement of an auction is not an offer but an invitation to treat.

Cross-offers do not create a binding contract without mutual acceptance