Climate change will have a progressively increasing impact on environmental degradation and environmentally dependent socio-economic systems with potential to cause substantial population displacement. The key concerns in Less Developed Countries (LDCs) will include serious threats to food security and health, considerable economic decline, inundation of coastal areas, and degradation of land and fresh water resources (Reuveny in Polit Geogr, <CitationRef CitationID="CR52">2007</CitationRef>). The relationship between environmental change and potential humanitarian crises has been captured by: McGregor (Geography and refugees: patterns and processes of change, Belhaven Press, London, pp 159–70, <CitationRef CitationID="CR41">1993</CitationRef>), Kibreab (Environment and Population Change, International Union for the Scientific Study of Population, Liège, <CitationRef CitationID="CR32">1994</CitationRef>), Kibreab (Disasters 21(1):20–38, <CitationRef CitationID="CR33">1997</CitationRef>), Myers (Bioscience 43:752–761, <CitationRef CitationID="CR42">1993</CitationRef>), Myers and Kent (Environmental exodus: an emergent crisis in the global arena, Climate Institute, Washington, DC, <CitationRef CitationID="CR45">1995</CitationRef>), Black (New Issues in Refugee Research, Working Paper no. 34, <CitationRef CitationID="CR10">2001</CitationRef>), Lee (Environmental matters: conflict, refugees and international relations, World Human Development Institute Press, Seoul and Tokyo, <CitationRef CitationID="CR36">2001</CitationRef>), Castles (Environmental Change and Induced Migration: Making Sense of the Debate Working Paper No. 70, <CitationRef CitationID="CR11">2002</CitationRef>), Christian Aid (Human tide: the real migration crisis, Christian Aid, London, <CitationRef CitationID="CR13">2007</CitationRef>), and Massey et al. (<ExternalRef> <RefSource>http://www.psc.isr.umich.edu/pubs/pdf/rr07-615.pdf</RefSource> <RefTarget Address="http://www.psc.isr.umich.edu/pubs/pdf/rr07-615.pdf" TargetType="URL"/> </ExternalRef>, <CitationRef CitationID="CR40">2007</CitationRef>). However, we know little about the interplay between environmental change and stresses on ecological systems, resulting socio-economic vulnerability and potential outcomes in terms of population displacement or induced migration. So far these relationships are poorly conceptualized, lack systematic investigation, and are reduced to simplistic causal explanations. This leads to misleading conclusions that deny the complex multivariate processes—environmental, political, social, and economic— which are the root causes of environmentally induced migration and/or conflict. When people are faced with severe environmental degradation they have one of three options: (1) stay and adapt to mitigate the effects; (2) stay, do nothing and accept a lower quality of life; or (3) leave the affected area. The process of movement and migration is usually subject to a complex set of push and pull forces, where push forces relate to the source area while pull factors relate to the destination. These forces are in constant flux, as much as environmental change, and interact with socio-economic and political conditions including state or government decision making powers, which can tip the balance at any point by either denying movement or the right to settle elsewhere. The paper focuses on how environmental change and environmental hazards contribute to the migration by exploring the mechanisms through which vulnerability and migration are linked—via livelihoods, relocation policies, and other factors. The paper begins by outlining important definitions of what is environmentally induced migration. The paper also considers the question of whether migration is a process that reduces or increases vulnerability. The paper draws on multidisciplinary literature including ecology, environment, and climate change; sociology of migration; anthropology of displacement; and economics; but also on preliminary from various case studies in Egypt, Vietnam, and Mozambique. Copyright Springer Science+Business Media B.V. 2010