A model to determine pasture value index (PVI) was developed for use on the semiarid rangelands of Senegal which are stocked with a mixture of cattle, goats and sheep. The model included selection by animal type, geographical distribution of vegetation resources and abiotic factors such as accessibility of water. Data were obtained from plots grazed by cattle, sheep or goats or by all 3 grazing animals in 1990-92. PVI values were highest for cattle and lowest for goats. There was considerable diversity between grazing areas and in their potential value for different grazing animals but the results were dependent on factors such as distance from water and shelter. Planned further development of the PVI is outlined. (CAB Abstract)