The Exclusion Argument has afflicted non-reductionists for decades. In this article, I attempt to show that emergentism—the view that mental entities can downwardly cause physical entities in a non-overdetermining way—is the most plausible approach to solving the exclusion problem. The emergentist approach is largely absent in contemporary philosophy of mind, because emergentism rejects the Causal Closure of Physics, a doctrine embraced by almost all physicalists. This article, however, challenges the consensus on causal closure and defends a physicalist version of emergentism. (...) On closer examination, I find that neither physical evidence nor physicalist considerations can satisfactorily support causal closure. Moreover, I argue that two competing approaches that accept causal closure, compatibilism and autonomism, involve ad hoc postulations of mental causation. Therefore, all things considered, emergentism is the best option available to non-reductive physicalists. (shrink)