Chapter 1 asks why any particular state’s law should have authority outside its geographical territory, and particularly in cyberspace. A state’s constitution is not binding on cyberspace users outside its territory and thus cannot give its laws any collective authority, as a legal system, in cyberspace. Law therefore must derive from acceptance by cyberspace users of a particular state law’s authority. But this does not confer general authority on the other laws of the state. This means that lawmaking authority in cyberspace has to be assessed at the level of individual rules of law, not at the law system level. Each rule derives its authority from acceptance by those it claims to regulate. It thus has authority over the members of the lawmaker’s extended community in cyberspace, but that community is dynamic and constantly changing. So a law has authority over a cyberspace user only whilst that user is a community member.