The globalized and decentralized Internet has become the new locus for a wide range of human activity, including commerce, crime, communications and cultural production. Activities which were once at the core of domestic jurisdiction have moved onto the Internet, and in doing so, have presented numerous challenges to the ability of states to exercise jurisdiction. In writing about these challenges, some scholars have characterized the Internet as a separate “space” and many refer to state jurisdiction over Internet activities as “extraterritorial.” This article examines these challenges in the context of the overall international law of jurisdiction, rather than focusing on any one substantive area. This article argues that while the Internet may push at the boundaries of traditional principles of jurisdiction in public international law, it has not supplanted them. The article explores the principles of jurisdiction, including the evolving concept of “qualified territoriality,” and demonstrates how these principles continue to apply in the Internet context. The article examines how states exercise their authority with respect to Internet activities by addressing governance issues, by engaging in normative ordering for the Internet, and by extending the reach of their domestic laws to capture Internet-based activities. Lastly, the article concludes by offering a set of “first principles,” in the form of policy precepts, to guide the evolution of public international law norms and to address problems particular to the context of the global Internet.