This paper studies the relationship between promoting people's welfare and respecting their autonomy of choice under risk. I highlight a conflict between these two aims. Given compelling assumptions, welfarists end up disregarding people's unanimous preference, even when everyone involved is entirely rational and only concerned with maximizing their own welfare. Non-welfarist theories of social choice are then considered. They are shown to face difficulties, too: either they fail to respect the value of welfare in at least one important sense, or (...) they end up prioritizing different people's welfare differently in non-risky choices, on the basis of their attitudes to risk, which are intuitively irrelevant in this context. (shrink)