This essay offers an alternative account of Leibniz’s views on substance and fundamental ontology. The proposal is driven by three main ideas. First, that Leibniz’s treatment should be understood against the backdrop of a traditional dispute over the paradigmatic nature substance as well as his own overarching conciliatory ambitions. Second, that Leibniz’s metaphysics is intended to support his conciliatory view that both traditional views of substance are tenable in at least their positive and philosophical respects. Third, that the relationship between immaterial substances, corporeal substances, and ordinary bodies in Leibniz’s metaphysics is best understood as one of “material” constitution. The interpretation as a whole thus sugge...