The concept of autonomy plays at least two roles on moral theory. First, it provides a source of constraints upon action: because I am autonomous you may not interfere with me, even for my own good. Second, it provides a foundation for moral theory: human autonomy has been thought by some to produce moral principles of a more general kind. This paper seeks to understand what autonomy is, and whether the autonomy of which we are capable is able to serve these roles. We would naturally hope for a concept of autonomy that is value-neutral rather than value-laden. That is to say, we would want the judgement that I am autonomous to depend wholly on, say, structural features of my psychology, and in no way to require us to make ethical judgements, or other value judgements. Being value-neutral is perhaps desirable in a concept of autonomy serving the first role, and plausibly indispensible in one playing the second. I shall argue, however, that value-neutral conceptions of autonomy are impoverished and out of line with our intentions; set out and defend an explicitly value-laden conception of autonomy; and explore the implications of such a view for the ability of autonomy to play the roles mentioned above.