Usenet is an international communications system composed of thousands of topically named discussion groups, called newsgroups, which enable anyone with an Internet connection and the proper software to read messages, post new messages, or reply to existing ones. Remarkable for its culture of ''anything-goes'' free speech, Usenet tradition recognizes only one kind of legitimate restriction on content: that which is abusive to the Net's ability to function as an effective discussion system. This article shows that this consensus stems from a long and often painful struggle, as Usenet's designers, administrators, and users attempted to comprehend, define, and govern the communication system they had created. The result is a forum that is not quite as free as Usenet's defenders like to imagine, and one given to excesses that seem destined to attract the attention of government censors.