 The principle of fidelity articulates a first-order duty to keep one’s promises, grounded not in the simple fact of promising, as on the bare reasons view, but in the fact that promises give assurances that lead to reasonable reliance and a risk of harm. The principle calls for doing as one has promised and not just making up a disappointed promisee’s losses, but it does not prescribe any specific legal enforcement scheme. Consequently, an important challenge for the view is explaining contract law’s standard remedy for breach, which obliges the promisor to vindicate the promisee’s expectation and not merely reimburse her for costs incurred through reliance.