Well-known for its high content on vitamin A, watercress is part of the greens widely consumed in the capital city of Madagascar and appreciated by the population. We can find two kinds of watercress' cultivation: the first one is grown in clear water in suburban area; the cultivation on terraces allows the water to be renewed regularly. The second one is located in poluted area with wastewater. Although the consumers concern about the production chain, the market remains stable. In fact, Qualisann project (Quality, Health and Nutrition), led by a multidisciplinary team from different universities, worked to ensure the quality of watercress and to evaluate risks for consumers and producers. This reserach suggests "How do consumers perceive the quality of the watercress and how to ensure the quality process by identifying the actors in the filiere and their role". A survey was conducted to understand consumers' perception of watercress quality, and the knowledge of the watercress plantation and the propensity to pay the quality of the watercress. A qualitative survey of 50 people was followed by a quantitative survey of 1,024 households. They provide the different quality criteria, the source of uncertainty of the quality and the actions from the consumers to face risks. Consumers adopt measures to prevent risks by washing and cooking before consumption. The study shows that consumers are responsible of their food safety. Their knowhow would be a significant contribution to deal with food healthiness. To increase 2 the efficiency of risk regulation, public information should be reinforced to limit asymmetric information.