The links between environmental change and migration is a theme which has caused much public debate. This debate is driven partially by the lack of empirical research on the linkages and relationship between environment and migration. This article offers a contribution to the limited literature which examines the ways in which migration is linked to environmental push factors. Initial research into the current dynamics of population displacement and migration linked to flooding in the upper reaches of the Vietnamese Mekong Delta was carried out in late 2007. Annual cyclical flooding in the Mekong Delta of Vietnam is a regular event and essential to the livelihoods of people living in the region. Over the last decade, however, there have been unusually large flooding events in the Mekong Delta region which have adversely impacted the lives and livelihoods of local communities. The research aimed to determine whether flooding could be considered a cause for migration or displacement. Results show that the impacts of regular flooding of the Mekong Delta can trigger independent household or individual migration decisions and are a cause for government-initiated resettlement of households. This research contributes to an increased understanding of the role of environmental change/degradation in causing displacement and migration, since forced migration and migration studies have more commonly focused on economic, political and social reasons for population displacement.