This paper addresses two questions. First can a binding promise conflict with other binding promises and thereby generate conflicting obligations? Second can binding promises conflict with other non-promissory obligations, so that we are obliged to keep so-called ‘wicked promises’? The answer to both questions is ‘yes’. The discussion examines both ‘natural right’ and ‘social practice’ approaches to promissory obligation and I conclude that neither can explain why we should be unable to make binding promises that conflict with our prior obligations. There is also consideration of the parallel case of ‘wicked commands’
