When a secessionist movement breaks out among an ethnic group that straddles an international boundary, it immediately affects the neighboring ethnic kin state--a neighboring state that contains co-nationals of the secessionists. Given the arbitrariness of international boundaries (primarily, but not exclusively, in the developing world), which often divides ethnic groups among two or more states, and the re-emergence of ethno-secessionist movements in the post-bipolar world, the likelihood of ethnic kin states being present next to a secessionist region and being involved in the conflict in some capacity is high. Understanding how ethnic kin states react to secessionist movements involving their co-nationals in neighboring states is, therefore, important because it usually holds the key to predicting the audibility, visibility, durability, and international acceptability of such movements. In this dissertation, I develop and test a series of hypotheses about the different policies an ethnic kin state may pursue towards a secessionist movement of co-nationals in a neighboring state, the various motives that drive each policy, the motives of a particular policy and the quality of response it generates, and the consequences of the various policies for the audibility, visibility, durability, and international acceptability of the secessionist movement
