This chapter examines the fiduciary duties of for-profit managers in modern liberal society. To arrive at the right “mix” of these duties, it compares the fiduciary duties implied by a standard descriptive model of our society with two competing normative models: Lockean libertarianism on the “right” and neo-classical republicanism on the “left.” This comparison shows that all three versions of liberalism, even the one with a Lockean night-watchman state, require far more extensive duties than we now expect, including a professionalization of management itself. And it shows that the version of liberalism with the most expansive state, neo-classical republicanism, requires the most appealing set of for-profit fiduciary duties. More basically, it concludes that what makes this latter set most appealing is that we ourselves are evaluating it from the perspective it recommends for for-profit managers: What is best, by our own best lights, for society as a whole.