Abstract: Debates over what is fundamental assume that what is most fundamental must be either a “top” level (roughly, the biggest or highest-level thing), or a “bottom” level (roughly, the smallest or lowest-level things). Here I sketch an alternative to top-ism and bottom-ism, the view that a middle level could be the most fundamental, and argue for its plausibility. I then suggest that this view satisfies the desiderata of asymmetry, irreflexivity, transitivity, and well-foundedness of fundamentality, that it is on par with the explanatory power of top-ism and bottom-ism, and that it satisfies the Principle of Sufficient Reason.