A first-phase development of a mathematical theory for a new modeling schema that is termed hierarchical holographic modeling is presented. This theory will provide a methodology for capturing and dealing with a fundamental, but heretofore neglected, characteristic of large-scale systems-their multifarious nature. Truly large-scale systems reflect a bewildering variety of resources and capabilities and respond to an equally wide variety of objectives in response to the action of diverse users. Many elements involved in this congeries of resources, objectives, actions, etc., are noncommensurable and, at least potentially, conflicting. Realistic attempts at modeling have necessarily represented commensurable features of limited aspects of the overall systems leaving many difficult questions of a more comprehensive nature to be posed and solved heuristically or even subconsciously. The prospective application of hierarchical holographic modeling to energy and water resources systems is discussed.