To the lawyer and non-lawyer alike, property is a ubiquitous phenomenon; we are surrounded by it, it dominates much of what we do, and its protection and regulation are among our legal system's most preeminent concerns. Exactly what property is, however, is a moot point. Can it be defined merely as ownership of objects, resources, or interests? Does property only exist when there is a right to exclusion over objects, resources, or interests? Does property connote not only rights, but also responsibilities? Are the limits of property circumscribed by social, moral, and technological factors? It can be said that there are no certain answers to these and many other questions relating to property. Correspondingly, there is no single definition of property-only an array of contested possibilities. Perhaps the only thing that can be said with certainty about property is that it is an essentially contested concept par excellence.