Flood retention areas are being increasingly promoted for flood risk management. People living in these areas will accept them if their interests are taken into account. The present study analyses the extent to which farmers' interests were taken into account in two flood retention projects in Thailand. A feasibility study was conducted in preparation for the first project which included public participation. The second project was a pilot project implemented in the same zone at a small scale. Participants in the public participation process and farmers living in proposed flood retention areas were interviewed for the purpose of the present study. Agreement could have been reached between the farmers and the public agencies concerning the flood retention areas. However, the participation process did not enable frank discussion about the conditions under which farmers would accept the project. The second project was designed without public participation and offered very little compensation to farmers. In countries marked by power imbalances in water resources management, public agencies may impose flood retention areas, but the absence of agreements with farmers can reduce the effectiveness of the measure. Reaching such agreements requires challenging the imbalanced power relationships between farmers and public agencies.