You would not expect a court to force your friend to buy you a coffee just because she promised. Yet you would expect a court to enforce a signed lease for a shop. What makes the difference? In English law, two more ingredients—on top of offer and acceptance—must be present to turn a promise into a binding contract: consideration and an intention to create legal relations. This chapter shows you how those filters work and introduces the rule that only the people who make the deal can usually sue on it, along with an important modern exception.