Thornton v Shoe Lane Parking Ltd (1971) affirmed that terms must be clearly communicated before a contract is formed. When a ticket issued by an automated machine attempted to exclude certain clauses, the court held it ineffective as contractual terms cannot be imposed post-acceptance.
Timing of Contractual Terms: Contractual terms must be presented and accepted before or at the time of contract formation. Any terms introduced after acceptance, such as on a ticket issued by a machine, are invalid. This principle ensures fairness in contract formation.