The non-identity problem arises when an intervention or behavior changes the identity of those affected. Delaying pregnancy is an example of such a behavior. The problem is whether and in what ways such changes in identity affect moral considerations. While a great deal has been written about the non-identity problem, relatively little has been written about the implications for physicians and how they should understand their duties. We argue that the non-identity problem can make a crucial moral difference in some (...) circumstances, and that it has some interesting implications for when it is or is not right for a physician to refuse to accede to a patient's request. If a physician is asked to provide an intervention (identity preserving) that makes a person worse off, then such harm provides a good reason for the physician to refuse to provide the intervention. However, in cases where different (identity-altering) interventions result in different people having a better or worse life, physicians should normally respect patient choice. (shrink)