Efforts to properly manage forage resources on our nation's rangelands led to development of the ideas: "carrying capacity" and "stocking rate." Carrying capacity refers to how many and how long livestock can be placed on an area of land without damaging the ecosystem. Stocking rate is the density of livestock (animalsIacre) for a given unit of time, and is generally determined by management objectives and estimates of carrying capacity. Because several species and types of grazing animals are used by livestock producers, attempts have been made to develop a standardized animal unit so that differences in forage demand across animal physiological classes and among species could be expressed on a common basis. A mature nonlactating 1100 lb beef cow is an animal unit. Ratios of other species and classes compared with an animal unit are called animal unit equivalents (AUE's). Animal units are currently used as a basis for grazing fee assessments on private and public lands, and for economic assessments such as appraised value of a ranch or its loan value. Due to the possibility of increasing costs charged by Federal and State agencies for an animal unit, there is a need to examine animal unit equivalents for accuracy so parity can be ensured. This paper will examine the development of AUE's for sheep and suggest a change to the current system.