For more than one decade now, and partly as a response to European Commission directives, the French government is promoting a transition of agriculture to agroecology. Agroecology is here considered as a mode of agricultural production that is able to reconcile economic, environmental and social performances at the farm level. The national governmental plan ECOPHYTO is targeting a drastic decrease in the reliance on pesticides. This plan is one component of the ‘Agroecological project for France’ launched in year 2012, which is pointing out a systemic vision of technological changes. Even though these governmental initiatives were not successful in transforming the agriculture of the country so far – maybe because they had to face severe reluctances from some (not all) major farmers organizations –, they launched several interesting projects, among which the DEPHY farm network. This network is composed of 3000 volunteer farmers, working in a peer-to-peer mode with the help of advisers to demonstrate that it is possible to reduce the reliance on pesticides while maintaining – or even enhancing – the economic vitality of the agricultural sector. The first major result from DEPHY was that differences in strategical options, based on various combinations of crop management techniques designed at the farming system level, explained most of the huge differences in the pesticide input level across framers, for similar production situations. The second – significant – result was that, in most production situations, those farms with agroecology-based cropping systems produced similar or even higher levels of agricultural outputs (incidentally more diversified), and similar or higher profits, as compared to standard farms based on high chemical inputs. Scale matters very much in those results, as what is true at the farm level might be quite different at the crop level. For example, wheat yields (expressed as tons per ha) were shown to be lower in low input management systems, because technical measures decreasing pest pressures (late sowing with resistant cultivars and moderate fertilization) tend to decrease also the yield potential. However, the decrease in wheat yield could be compensated for by the decrease in input costs, and could be considered a minor feature for farm profitability. Based on such results, the DEPHY network is promoting changes in the way of advising farmers, more focused on long term and systemic approaches, and targeting explicitly farm profitability rather than individual crop yield. Of course, agroecology-based farming systems increases the complexity of farm management. Pioneer farmers of the DEPHY network are not representative of farmers’ population. They are well educated and do invest a lot in knowledge acquisition and peer-to-peer training. They most often also show a high motivation for their job and for communicating about their personal experience. Upscaling the results of the DEPHY network at the country level provided information about the potential consequences of the widespread adoption of agroecology-based cropping systems in France. Pesticide use would decrease by about 40%. The overall agricultural production would increase, but wheat and barley production (and therefore exports) would decrease (partly because of lower yields, mostly because of a decrease in areas sown with wheat and barley). The local production of plant proteins for cattle feeding would increase, hence decreasing the need for foreign protein import. This, along with the decrease in fertilizer inputs, would offset the decrease in cereal export, and the overall agricultural trade balance would improve at the country level. These results are questioning the model of a trade balance mostly boosted by cereal exports. That is the main reason why the current organization of the agricultural sector (based on targets of minimizing diversity, maximizing yield to maximize exports) is a major hindrance for any large-scale adoption of agroecology-based farming systems. Nicolas Munier-Jolain is an agronomist of cropping/farming systems at INRA, research unit Agroecology, in Dijon, France. For more than two decades, he has been working on the issue of decreasing the reliance on pesticides in arable cropping systems in France, focusing mostly on weed management. His research on Integrated Weed Management is based on experimental activities (long term cropping system experiments), modelling weed communities as affected by cropping systems, and data mining using data sets produced by participative farm networks. Since 2011, he has worked with the farmers and advisers involved in reducing pestici