`Non-repudation' is a favourite buzzword in e-commerce discussions, and a major part of much new digital signature legislation. But its use outside its original security context is riven with problems. This talk looks at the technical, usability, and legal difficulties associated with non-repudiation in the real world, and their effect on the allocation of risk in e-commerce. Banks have successfully moved the risk of online credit card transactions to merchants. Can they shift banking risk to consumers so easily?