The objectives of the study were to establish the challenges the Maasai pastoralists experience when engaging in cross-border movement, the measures to facilitate cross-border movement, and establishing the importance of informal cross-border movement. The theories used to expound the study were intergoverntalism, and relative deprivation theory. A sample of 80 respondents was used to give information on the status of social and regional integration between the two countries. The findings were that the current status of social and regional integration between the countries was 62.8% satisfactory, cross-border movements by pastoralists promote social and regional integration (69.7%), and that free movement of goods and services fostered strong integrated community between the two countries (79.2%). The challenges identified were the stiff customs and border procedures (60%), limited border checkpoints (56.9%), unequal enforcement of the standards of compliance (57%), and informal restrictions (63.8%) were mentioned as major challenges of informal cross-border movements among the pastoralists. The respondents also mentioned other key problems of the changing land tenure (28.75%), increasing demand for land (70%), and lack of adequate investment in the dry lands to control the livestock resources (pastures and water (51.3%). The measures suggested were adequate community participation; Mainstreaming resources based conflicts, and establishing and supporting cross-border exchange programs for the pastoralists. The cross-border movements were associated with promoting unity, international relations and creating stronger economies. It was recommended that the two governments engage in dialogue to further strengthen the relationship between the two countries. Policy formulation was also a suggested help in controlling the movement of the pastoralists across the borders. Key study terms: informal cross-border movement, regional integration, social integration, Maasai, pastoralists