Humans are among the most intelligent species, using powerful cognitive abilities to develop sophisticated language and culture and to expand beyond their original range to all corners of the Earth. Similarly, humans are remarkably social, building elaborate social structures characterized by substantial division of labor and coordination in activities without the need for tight genetic relatedness. In this chapter, we review research that not only connects these abilities, but suggests that they are mutually dependent. We begin by reviewing the social brain hypothesis—a prominent evolutionary explanation for our high intelligence. We then discuss how the social brain manifests in specific brain structures with distinct consequences for social behavior and, by extension, social networks. This segues to current thinking about the activity at the level of minds, which extends the capabilities manifest in brains, enabling the formation and maintenance of complex social networks that might otherwise exceed humans’ cognitive capacity. Finally, the chapter concludes with a consideration of what we know as well as what directions researchers should pursue in the future at the intersection of neuroscience, cognition, and networks, and why they should do so.