 While much of the early work on ontological dependence was done primarily in a setting where dependence was thought to be an inherently modal notion (e.g., Simons 1987), the recent trend in hyperintensional metaphysics (see Nolan 2014) has had an enormous impact for discussion surrounding dependence. The thought here is that we need more fine-grained tools than mere necessary equivalence: two statements can apply to the very same entities across all possible worlds but not be equivalent. Here, the notion of essence is often invoked, and many would now regard the ultimate basis of dependence (and indeed of modality itself) to be essence (see Fine 1994a, Lowe 1998, Correia 2005, and Koslicki 2012). Finally, it is entirely possible to deny both approaches and regard the notion of ontological dependence itself as a primitive (see Thomasson 1998: Ch. 2 and Barnes 2012: 879). Some would regard the notions of metaphysical grounding or fundamentality to be similarly primitive (see Fine 2012, Rodriguez-Pereyra 2005, Rosen 2010, Schaffer 2009, and Wilson 2014). Primitivism does not mean that the notion is mysterious or obscure, as we can still illuminate it, e.g., by describing its instances. But it does mean that the notion is unanalyzable.