This essay examines the dynamics of the face-to-face inter-ethnic relationship in a multi-ethnic situation among pastoralists of Northern Kenya. Segmentary descent system is a well known characteristic of East African pastoral society as a means of social interaction (Evans-Pritchard, 1940). As a charactaristic of these systems, each segment (ethnic group, clan, sub-clan, lineage) according to patrilineal descent is sequenced in a highly hierarchical way, and categorizes people clearly with behavior norms (marriage, cohabitation, cooperation etc.). Clanship is especially important in every aspect of their lives. The Ariaal in the Mars abit district of northern Kenya have been reported as being a mixture of the Samburu and Rendille pastoralists as the historical result of migration and alliance between them (Spencer, 1973; Fratkin, 1991). Both the Samburu and Rendille societies have their own segmental descent system. In the Ariaal, people choose parts of both the Samburu and Rendille segmental descent systems. The subject of this essay is the process by which people dismantle preexisting categories and reconstruct them. People have a sense of belonging to their clan, but it depends on the relationships, which are made in two ways. One way creates a sense of belonging by depending on the relationship between segments, including clans. The other way is to create a sense of belonging by depending on individual experience. People create a sense of belonging individually by sharing the experience of cooperating in herding, settling and ceremonies. People can create a sense of belonging somehow by depending on the relationship between segments. This sense of belongingness by depending on the segments as a social category can be interpreted and manipulated in any form. Then, such a category itself would lose actual meaning. It is assumed that people will continue to believe in their descent system, but also create a new sense of belongingness based on shared personal experiences.