<p>Howard Robinson has criticized the contemporary revival of hylomorphism for, on the one hand, accepting the causal closure of the physical, while, on the other, ascribing a real and irreducible causal role to forms or structures. If the world is causally closed under physics, it makes no sense to postulate a structure that actively affects the distribution and motion of matter. After carefully formulating what I call Robinson’s <i>causal closure argument against hylomorphism</i>, I demonstrate that the argument fails because it presupposes an overly strict conception of causal closure of the microphysical, according to which every physical effect is completely determined by, and has a complete explanation in terms of, bottom-level microphysical entities and their interactions governed by fundamental physical laws. Based on two case studies – one from physics (the Fractional Quantum Hall Effect), the other from microbiology (information control in microorganisms) – I argue that the argument fails, yet a more modest (and scientifically defensible) version of closure remains intact. This version of closure secures that no non-physical forces supplement the inventory of fundamental physics while allowing higher-level constraints to be causally efficacious by constraining which among multiple microphysically compatible possibilities is actualized. This means that a reformulated version of closure, capable of dealing with those cases, is also perfectly compatible with the hylomorphist (or generally anti-reductionist) claim that higher-level structures are causally efficacious and an irreducible part of physical reality.</p>