Key environmental challenges faced by the aquaculture sector demonstrate that aquaculture production is not isolated from the surrounding environment, and we see a policy shift towards area-based approaches. However, without an understanding of the farmer's perspective, there is a danger of misrepresenting how farm-level practices relate to area-based approaches and to environmental risk management. This paper empirically examines how individual aquaculture farmers interpret and manage environmental risks and the extent to which they operate beyond the boundaries of their farms. The analysis is based on a comparison between intensive aquaculture farmers in Kung Krabaen Bay, Thailand, representing an area of closed production systems; and a mixture of integrated mangrove shrimp and extensive shrimp farmers in Kien Vang Forest, Vietnam, representing an area of open production systems. Data were collected through semi-structured interviews and participatory mapping.