Some suggest that gene editing human embryos to prevent genetic disorders will be in one respect morally preferable to using genetic selection for the same purpose: gene editing will benefit particular future persons, while genetic selection would merely replace them. We first construct the most plausible defence of this suggestion—the benefit argument—and defend it against a possible objection. We then advance another objection: the benefit argument succeeds only when restricted to cases in which the gene-edited child would have been brought (...) into existence even if gene editing had not been employed. Our argument relies on a standard account of comparative benefit which has recently been criticised on the grounds that it succumbs to the so-called ‘pre-emption problem’. We end by considering how our argument would be affected were the standard account revised in an attempt to evade this problem. We consider three revised accounts and argue that, on all three, our critique of the benefit argument stands. (shrink)