I examine the current state of the debate on the metaphysics of science. In 1, I identify some of the main questions belonging to the MS, looking into the relationship between science and metaphysics. In 2, I expound the rise of the old wave in the MS, which endorses the belief that metaphysics is a guide to, or a heuristic for, science and outlines the stronger idea that metaphysics makes science possible. In 3, I examine the maximalist MS. This is (...) a contemporary revival of the old wave, reformulating the claim that metaphysics makes science possible. In 4, I look into the new wave in the MS, which argues that science is a guide to metaphysics and, more radically, that metaphysics is to be motivated by, and restricted to, science. In 5, I briefly introduce my own minimalist MS, which contends that science sets the epistemic, methodological and ontological criteria which should work as desiderata of the MS. I close this chapter in 6 with some concluding remarks. (shrink)