Contemporary takings scholarship has devoted much attention to the problem of regulatory takings and has largely assumed that physical takings are resolved under a clear but simplistic per se rule. Under that rule, modern courts automatically find a physical taking whenever government action causes a permanent physical invasion of property, regardless of the context or the importance of the public interest. Applying this bright-line rule has proved to be difficult because it ignores the nuances of physical takings situations and the complexities of modern property arrangements. Should the physical takings concept apply to a rent control law that limits the ability of landlords to exclude tenants, to temporary but deliberate breaches of a le...