This chapter examines the key cases and principles relating to acceptance. Where an offer has an essential requirement relating to acceptance (like the method of acceptance) then it must be followed. However, equivalent alternatives might be permitted if the offeror has not done enough to make the requirement essential. Acceptance must be in response to an offer, but the motive for accepting is not relevant. The general rule is that acceptance is effective once it has been communicated (received). Automated ticket and vending machines present an offer so that acceptance takes place when the customer is committed—as when payment is made. Meanwhile, emailed acceptance and the use of websites to communicate acceptance are likely to operate on the basis of the general rule. The traditional analysis based on offer and acceptance will be applied to ‘battle of forms’ cases. In exceptional cases, courts may look to the wider context in such cases to identify the terms of an agreement.