The central problem of this thesis is one of explaining the complex nature of the kinship system of the Meidob, a small tribe of pastoralists living in the north-east of Northern Darfur Province, Republic of the Sudan. The system is unusual in that there is recognition of three different types of kinship group, the matriclan, the patriclan., and the group of descending kindred. This study also attempts to look at the way in which kinship networks function in such a highly segmented and fluid population as that of the Meidob, and to solve certain anomalies such as the wide dispersal of co-wives, and the central role that co-resident daughters and their children play in what is dominantly an agnatically orientated society. The solution to these and other problems is found through a detailed analysis of marriage and residence . Through looking at patterns of marriage within the kin group, and at the process of establishing a new household, the way t hat the different groups come into play is made apparent. By studying residence patterns and their association with different stages of the developmental cycle, one gains an insight into the ways in which the conflicting ties of matri- and patri- kin come into effect. One of the crucial factors to the functioning of this system would appear to be that of polygyny and its associated residence patterns These demonstrate how the polygynous union does not have the expected result whereby a man expands his co-resident.family group . Instead we find that the dominantly virilocal pattern of first marriage assures agnatic continuity, whereas the separate residence of secondary spouses allows for the maintenance of cognatic family ties and the development of groups of descending kindred. Finally, by looking at the distrilution of these kin groups in terms of the localised cluster of hamlets, it is possible to see the consequences of these patterns of marriage and residence in terms of the development of localised and dispersed kin groups.