N° ISBN - 978-2-7380-1284-5International audiencePopulation growth in the Languedoc coastal region is very high since few decades. This phenomenon produces a rapid and uncontrolled urban sprawl at agricultural lands expense. While these lands are often high agronomical potential, they are most often permanently lost. To better understand the dynamics of consumption of these agricultural lands by artificial surfaces and to have spatial tools to argue the risk of permanent loss of agronomical potential heritage, the Regional Direction of Food, Agriculture and Forestry of Languedoc-Roussillon has commissioned a study from research institutions: INRA for the agronomical theme and Cemagref for the spatial information and analysis. In order to quantify and qualify agricultural land changes, a methodology intended to build a system of spatial and spatialized indicators is being developed. The appropriation of indicators by users is the guarantee of their use. Research has therefore relied on an iterative participatory approach for the co-construction and the co-evaluation of indicators by stakeholders. The paper aims to present and discuss the approach and methods used for the production of indicators. More generally, it's a contribution to analyze process of consultation intended to develop measurement and decision-making tools