My dissertation is about qualitativism, the view that the facts constituting the world are, fundamentally, purely qualitative or general. Roughly, non-qualitative facts directly involve particular things (e.g. the fact that Obama is human), whereas qualitative facts do not (e.g. the fact that something is human, or that humanity is instantiated). One might get a handle on qualitativism through this metaphor: to create the world, God would not decree any nonqualitative facts; once the qualitative is decreed, the non-qualitative is thereby determined. Robert Adams put qualitativism on the table in an influential 1979 article, and the thesis has recently received significant attention. My main aim is to defend qualitativism, though I also have a bit to say about how it should be understood, and about its connections with other metaphysical topics. Here I will touch on the three main lines of thought that I pursue. It is initially natural to think that qualitativism is incompatible with the idea that there could have been a pair of qualitatively indiscernible but numerically distinct individuals. This would be a problem for qualitativism, inasmuch as many find it intuitive that there could be such a pair. (Imagine, for example, a spatially symmetric universe containing just two iron spheres, a and b, that perfectly resemble each other.) Recent work on qualitativism affirms its compatibility with this kind of possibility, but I do not think that such compatibility has been sufficiently justified. So I seek to do so, thereby resolving the apparent problem. The main challenge is to explain how the identity properties of the relevant individuals (for example, the property of being a and the property of being b) could be determined by purely qualitative matters, despite those individuals' indiscernibility. I develop a novel proposal for meeting this challenge (with some conceptual antecedents in work by Kit Fine and Shamik Dasgupta) that involves taking the properties to be qualitatively determined in a holistic fashion. It is also initially natural to think that qualitativism is incompatible with haecceitism, the view that there are some pairs of qualitatively indiscernible but numerically distinct possible worlds. This would be a problem for qualitativism, inasmuch as many find it intuitive that there are such pairs. (Consider, for example, a world in which sphere a exists for five seconds and sphere b for six, and a world in which b exists for five seconds and a for six.) Here I part company with recent work on qualitativism by denying such incompatibility: I propose a novel account of qualitativism that would render it compatible with haecceitism. The key idea turns on a notion of what I call an "ultimately qualitative" fact. A non-qualitative fact is ultimately qualitative if every constituent by virtue of which it is non-qualitative has a qualitative "real definition". By only requiring the fundamental facts to be ultimately qualitative, as opposed to qualitative, the qualitativist can accept haecceitism. I also argue that this account of qualitativism is independently motivated by reflections about the nature of time, and that prominent arguments for qualitativism do not discriminate between the novel and traditional account. With that said, I do not argue that qualitativism as traditionally understood is false, and I explain how haecceitism can be resisted. If I am on the right track with these two broadly defensive lines of thought, some important hurdles to a serious consideration of qualitativism are overcome. In the third main part of the dissertation, I develop a novel positive line of argument for qualitativism. I argue that qualitativism accords better than any other theory of the world's fundamental structure with the multi-location ban, i.e. the common-sense judgment that individuals cannot be located in multiple places at the same time. More precisely, I argue that (1) the multilocation ban gives us reason to affirm some theory of the world's fundamental structure according to which the identities of individuals are fundamentally extrinsic, and that (2) this proposal is best implemented in terms of qualitativism.