Welfare figures prominently in theories of value. In fact, some theories of value – those that are “welfarist” – maintain that welfare is the only fundamental intrinsic good. Non-welfarist theories must account for the nature and value of welfare as well, since the job of a complete axiological theory is to discover not only what things are good simpliciter, but what things are good for a subject. It is precisely the theory of welfare that does this job.