Migration now features prominently both in poverty-reduction discourses, as a 'tool' for reconciling rural populations with available resources, and in sustainable livelihoods debates, as a 'coping strategy' employed in times of livelihood stress. This paper assesses the contemporary significance of migration as populations are affected by the dual impacts of natural environmental variability and structural land-use change in the Kalahari of Botswana. Three study areas, located across the arid to dry-sub-humid climatic gradient, were investigated. These had been redesignated as commercial ranching areas under the Tribal Grazing Lands Policy of 1975. Under this policy, pre-existing populations were to be resettled in specially designated Service Centres that were expected to reduce poverty and improve livelihood opportunities and household food security. The findings of this study reveal that the policy was accompanied by extensive population displacement rather than migration per se as ranch owners exercised their exclusive rights to the land. While some ranch populations moved to Service Centres, lack of infrastructure and alternative livelihood opportunities forced many of them back into ranch areas where many now live as squatters dependent on the goodwill of ranch owners. Thus the policy has not resulted in envisaged sedentarisation but instead has produced a population of transients involved in a number of highly localised moves. The mobility patterns of absent householders provided some evidence to suggest that, despite rapid urbanisation, rural to urban migration from the study areas was limited, as were associated remittance flows, suggesting that TGLP areas may not be currently integrated within a national migration system. There were significant differences in the implementation of the policy between study areas and these differences have had a considerable bearing on the population's ability to respond to environmental variability. In one of the Study Areas (Ncojane), severe drought has resulted in a more flexible implementation of ranches: fences had been taken down, and people and cattle were able to move between ranches in search of water and veld products. Population mobility here was thus a significant coping strategy, ironically where commercial ranch owners had reverted back to the old cattle-post system which emphasises circulation and reciprocity.