This contribution aims to present issues from a survey carried on within the French institution 'INAO'(Institute for Denomination of Origin) which is in charge of the implementation of the EC regulation about Protected Denomination of Origin. The main objective is to observe the qualification processes of products and 'terroirs' used by the INAO's agents and to analyse their coherence with regard to the diversity of products, INAO's agents most often agree with each others to common choices of homogeneously defined concepts of Denomination of origin. Netherthe- less, some concepts are quite difficult to define and to use on an homogeneous way, such as 'terroir'.
