The last fifteen years has seen a rise in both the importance and the strength of intellectual property rights in the world economy; rights have expanded in areas ranging from the human genome to the Internet and have been strengthened with legally backed digital fences, lengthened copyright terms and increased penalties. Is this expansion of intellectual property necessary to respond to new copying technologies, and desirable because it will produce investment and innovation? Must we privatize the public domain to avoid a “tragedy of the commons,” or can the technologies of cheap copying and global networks actually make common pool management more efficient than legal monopolies? Questions such as these have thrown attention on the “other side” of intellectual property: the public domain. What does the public domain do? What is its importance, its history, its role in science, art, and in the building of the Internet? How is the public domain similar to and different from the idea of a commons? This conference, the first major meeting to focus squarely on the topic of the public domain, will try to answer some of these questions in areas ranging from the human genome to appropriationist art, from the production of scientific data to the architecture of our communications networks. For each panel, “focus papers” will be produced by authorities in the field and made available on the Internet before the event in order to generate discussion.