Plato, Aristotle, Kant, Brentano, Moore, and Chisholm have suggested marks or criteria of intrinsic goodness. I distinguish among eight of these. I focus in this paper on four: (a) unimprovability, (b) unqualifiedness, (c) dependence upon intrinsic natures, and (d) incorruptibility. I try to show that each of these is problematic in some way. I also try to show that they are not equivalent – they point toward distinct conceptions of intrinsic goodness. In the end it appears that none of them is fully satisfactory. Insofar as none of these succeeds, a fundamental problem remains for those who make use of the concept of intrinsic value. Precisely what do we have in mind when we say that some sort of value is intrinsic?