A public entity must ensure that individuals with disabilities are not excluded from services, programs, and activities because existing buildings are inaccessible. A State or local government's programs, when viewed in their entirety, must be readily accessible to and usable by individuals with disabilities. This standard, known as "program accessibility," applies to facilities of a public entity that existed on January 26, 1992. Public entities do not necessarily have to make each of their existing facilities accessible. They may provide program accessibility by a number of methods including alteration of existing facilities, acquisition or construction of additional facilities, relocation of a service or program to an accessible facility, or provision of services at alternate accessible sites.