This article addresses the question of the effect of an "organic and fair trade" double label for consumers by using experimentation on organic and fair trade chocolate based on,I bidding principle (Becker-DeGroot-Marschak (BDM) mechanism). Our results show that the "organic and Fair trade" label adds value to organic and fair trade products. However. sensitivity to this label varies among consumers and the (willingness to pay) WTP for "organic and fair trade" products may be affected by the product's taste. More precisely cluster analysis shows that One group is not readily willing to pay more, a Second group is ready to pay more without conditions and a third group is ready to pay more but only if along with the label, the products taste is perceived as good enough.