Willful breach doctrine should be a major embarrassment to contract law. If the default remedy for breach is expectation damages designed to put the injured promisee in the position in which she would have been had the contract been performed, then the promisor's behavior – the reason for the breach – looks to be irrelevant in assessing damages. And yet the cases are full of references to “willful” breaches, which seem often to be treated more harshly than ordinary ones based on the promisor's bad/willful conduct. This chapter's explanation is that willful breaches are best understood as those that should be prevented or deterred because the parties have implicitly agreed that the promisor would not breach in those circumstances. When willfulness, so understood, is present, courts rightly award remedies that serve to deprive the promisor of any incentive to breach and to assure the promisee of getting her full expectation.