To understand the nature of reality, the foundational paradox that divides the quantum and classical worlds must be resolved. We hope to determine if there exists a universal theory that connects quantum mechanics to classical mechanics. There are several examples where, for some limit, quantum becomes classical. But, there is no mechanism to unify such examples. This challenge limits the scope of philosophical interpretations of quantum mechanics and our understanding of the nature of our universe. With two full-time postdocs, one funded by JTF and the other by CQT, we will gather and categorize various quantum-classical correspondences within the subfields of correlations and generalized-probability theories. We will focus on establishing a common technical foundation for comparative discussions between the two fields. We will determine, on a technical basis, how differing quantum-classical correspondences are related or not, and thus take significant steps toward determining whether a universal theory, that connects the quantum and classical worlds for these subfields, exists. Our deliverable, as 4 peer reviewed articles, will give a common technical and semantic scaffolding to classify the existing views, and allowing for a future unification, if it exists.