This article argues that one of the main arguments against metaphysical infinitism—the argument from vicious infinite regress—is unsuccessful. I suggest that a proper interpretation of the argument takes the charge against infinitism to be one of metaphysical insufficiency: without the fundamental facts fully grounding the rest of reality, derivative facts lack the necessary grounding base for their obtaining. I disambiguate the insufficiency claim by examining it from two different perspectives on the regress: the local perspective, which focuses on the obtaining (...) of the individual derivative facts, and the global perspective, which focuses on the obtaining of the entire collection of derivative facts. For each perspective, I argue that the reasons for believing that infinitism cannot provide sufficient grounds are problematic. (shrink)