Pastoralism is an economic activity involving the care of herds of domesticated livestock. In its traditional forms it is either practiced as the main mode of subsistence or combined with agriculture. Pastoralism functions as a cultural system with a characteristic ecology. The community of the pastoralists can be considered in two dimensions, as an ecological unit and as a sociocultural community.Definitions . The pastoral community differs from natural animal communities in that it is subject to the cultural control exercised by man. Moreover, this pastoral community is something more than the sociocultural community. It is a selfperpetuating social group with a characteristic population size and composition, geographic locus and distribution, and in common with all other ecological communities, certain functional requisites for survival. This community has a set of institutions which relate it to a greater cultural whole, and in addition it maintains and is maintained by an inner conscious cohesiveness (see Arensberg 1961). But as members of a pastoral community, pastoralists also have sociocultural institutions through which they enter into mutually supportive relations with their herds and dependent or parasitic relations with the natural environment of their eco-system. In the same sense, pasture is not solely a natural phenomenon but is culturally controlled, being designated or delimited as individual, family, communal, tribal, or national property by pastoralists, who use it to provide natural sustenance to their herds.