Discovering obligations that are ascribed to them by others is potentially an important element in the development of the moral imagination of engineers. Moral imagination cannot reasonably be developed by contemplating oneself and one’s task alone: there must be some element of discovering the expectations of people one could put at risk. In practice it may be impossible to meet ascribed obligations if they are completely general and allow no exceptions — for example if they demand an unlimited duty to avoid harm. But they can still serve to modify engineers’ prior ethics, for example by limiting a purely utilitarian approach to deciding who should bear risk and how much risk they should bear. Ascribed obligations can also give engineers insight into the public reaction to risks that arise from engineered systems, and the consequent expectations that the public have about how much protection is desirable and where the responsibility for this protection lies. This article analyses the case for taking ascribed obligations seriously, and reviews some of the obligations that have been ascribed in the aftermath of recent engineering failures. It also proposes ways in which ascribed obligations could be used in engineers’ moral development.