The Internet is made up of interconnected Internet Protocol networks operated by different companies that conjoin bilaterally or at shared exchange points to form the global Internet. This chapter explains the architectural and market ecosystem of interconnection among these networks and presents some global policy issues related to interconnection. It first discusses autonomous systems and Internet exchange points (IXPs); the various types of networks that interconnect to collectively form the global Internet; and how Border Gateway Protocol (BGP) creates the standard technical basis on which interconnection among these operators occurs and introduces Internet exchange points. It then examines the economics of interconnection, explaining the various types of interconnection arrangements among companies that operate Internet networks. The concluding section presents several Internet policy circumstances at the Internet’s interconnection epicenter, including the prioritization of individual market incentives over technical efficiency; the uneven distribution of IXPs and associated interconnection challenges in emerging markets; and interconnection points as sites of control and disruption for government censorship and outages as a result of peering disputes.