The project of referring to localized cognitive operations in the brain has a long history and many impressive successes. This chapter describes the traditional project that refers to localized cognitive operations in the brain, and situates it within the framework of mechanistic explanations of psychological phenomena. It develops a different perspective on brain regions, one that construes them as active components in a dynamically self-organizing system. The chapter presents several sources of evidence that the brain exhibits small-world properties at multiple levels of organization. It examines evidence that small-world organization is also exhibited in the endogenous functioning of the brain and that functionally characterized small-world networks correlate with those characterized structurally. The chapter analyzes the history of localizing different steps in processing visual inputs in different cortical regions elsewhere. The behavior of a small-world network is extremely complex, and it is often only via simulation and the invocation of tools.