The four atoll states are quite different from each other in language, culture and political organisation. Tuvalu and Tokelau are part of Polynesia; the Marshall Islands and Kiribati are in Micronesia. Migration from Marshall Islands and from Federated States of Micronesia to the USA is possible under the terms of the Compact of Free Association; indeed the island states were anxious to ensure that such a clause be included in the compact. Rising sea-levels can only worsen, in a number of ways, the problems of achieving development in atoll states. It is apparent that there will be climatic changes in terms of differences in rainfall and storm frequency and rises in air and sea temperatures. Potentially increased emigration must be seen as one response to the Greenhouse Effect (GE), a response that builds on existing trends but unavoidably depends almost entirely on the policies of metropolitan states in the cases of Kiribati and Tuvalu and the other independent island states.