1. A method of specifying a first logical volume of a plurality of logical volumes in a networked computer system including a plurality of storage elements, a plurality of host computers, and a communications network, the plurality of storage elements and the plurality of host computers being coupled together by the communications network, wherein at least one of the host computers sends access requests to at least one of the plurality of storage elements to access data storage on the storage element, wherein each of the plurality of storage elements is a unitary storage system comprising at least one physical storage device and at least one controller that maps at least one logical volume to physical storage locations on the at least one physical storage device, wherein at least one of the plurality of logical volumes is stored on each of the plurality of storage elements, the method comprising acts of: assigning a logical volume identifier to the first logical volume, the logical volume identifier being assigned independent of the identity of the host computer initially creating the first logical volume and a physical storage location on the first logical volume and being usable by at least one of the plurality of host computers to access, via the communications network, the first logical volume on at least one of the plurality of storage elements, wherein the at least one of the plurality of storage elements makes the first logical volume available for access via its at least one port; and assuring that the logical volume identifier uniquely identifies the first logical volume among the plurality of logical volumes in the networked computer, wherein the logical volume identifier identifies the first logical volume when data thereof is stored at a first storage location in a first of said plurality of storage of storage elements and wherein the logical volume identifier identifies the first logical volume when data thereof is subsequently moved to a second storage location in a second of said plurality of storage elements different from the first storage element.