A scientific cooperation program between France and Vietnam in coastal oceanography was conducted between 2008 and 2010. This multidisciplinary program, Haiphong, aiming at studying the influence of anthropogenic and hydrological constraints on the diversity and functioning of the planktonic microbial trophic web in the Bach Dang estuary was funded by grants from the French Program on Coastal Ecosystems (EC2CO/PNEC), the Vietnam Academy of Science and Technology, IRD, and CNRS. This program allowed to gain scientific information on the physical functioning of this estuary (liquid and solid discharges, aggregation processes), its level of nutrient and contaminants enrichments (inorganic and organic nutrients, metals, organometals and chlorinated pesticides), and the diversity and functioning of the planktonic network (i.e. phytoplankton, bacterioplankton, virioplankton). In addition to this scientific information, this project promoted capacity building through in service training, master and PhD theses. This type of program has the benefit of providing tools useful to decision makers such as basis for developing (calibration, validation) circulation and transport models, and reference data onpollutants in a well-described physical context. The objective of this presentation is to provide an overview of the scientific data, with a special reference to those presenting the most effective potential for transfer to decision makers, and the capacity building achievements made during this project. This overview is aiming at favouring the definition of future collaborative projects between Vietnam and France in coastal oceanography.