In the span of one hundred years, the Borana pastoralist communities of Northern Kenya experienced relative changes and transformation in their social, political and economic life. During their almost seven decades rule (1890-1963), the British introduced a number of policies to facilitate political control and economic exploitation. In the subsequent three decades after independence (1963-1990), the Kenyan government also introduced social and economic policies to enable the integration of the pastoral economy into that of the nation. Although the policies under both regimes affected the life of the Borana, they neither led to a complete end to Borana nomadic pastoralism, nor did they bring the Borana too close to the center. The Borana responded to the policies innovatively neither totally rejecting them nor wholly incorporating them. This dissertation examines the social and economic impact of colonial and postcolonial state polices from the 1890s to the 1990s on the Borana. The study emphasizes how the Borana responded to the strategies through getting formal education, innovation in gender roles, engagaing in modern livestock trade, and migration and settlement in towns to earn cash and pay taxes. Through a critical examination of oral, archival and secondary sources, this dissertation concludes that the Borana were not passive recipients of system imposed on them by both regimes, but they adjusted their social and economic life to new realities that they encountered without totally abandoning their established livelihood. This study concludes that, despite the transformations that have taken place in the last century, pastoralism is still important to the Borana socioeconomic and cultural life. This study's findings suggest that the Borana neither completely rejected changes in their situation nor whole-heartedly incorporated them. They used patterns of accommodation and adaptation to balance their traditional ways of life with that of the new world to deal with internal and external forces of disruption. This has implications for post-colonial scholarship as well as Kenyan policymakers who have been dealing with recent political and social reforms.