I defend a new account of constitutive essence on which an entity’s constitutively essential properties are its most fundamental, non-trivial necessary properties. I argue that this account accommodates the Finean counterexamples to classic modalism about essence, provides an independently plausible account of constitutive essence and does not run into clear counterexamples. I conclude that this theory provides a promising way forward for attempts to produce an adequate non-primitivist, modalist account of essence. As both triviality and fundamentality in the account are understood in terms of grounding, the theory also potentially has important implications for the relation between essence and grounding