Packet switching networks provide rudimentary means to move units of "raw" data around. The Net can "transport," though it is unable to "manipulate" high-level content, video or audio sessions. Imagine what we could achieve with a network that is redesigned around what is the most precious thing in today's digital ecosystem: the content. This chapter introduces content-aware networks, ones that can re-route packets based on the content "usage patterns" and "requirements." We look at peer-to-peer networks as a practical example in order to better understand how to build content-aware networks on top of ordinary packet switching networks.