Vietnamese communities in the Mekong Delta are faced with the substantial impacts of rising sea levels and salinity intrusion. The construction of embankments and dykes has historically been the principal strategy of the Vietnamese government to mitigate the eects of salinity intrusion on agricultural production. A predicted sea-level rise of 30 cm by the year 2050 is expected to accelerate salinity intrusion. This study combines hydrologic, agronomic and behavioural assessments to identify eective adaptation strategies reliant on land-use change (soft options) and investments in water infrastructure (hard options). As these strategies are managed within dierent policy portfolios, the political discussion has polarized between choices of either soft or hard options. This paper argues that an ensemble of hard and soft policies is likely to provide the most eective results for people’s livelihoods in the Mekong Delta. The consequences of policy deliberations are likely to be felt beyond the Mekong Delta as levels of rice cultivation there also aect national and global food security.