In 2008, the French government announced an important shift in agricultural policy, calling for halving the use of pesticides in the next ten years. Since then, it has spent 40 million euros a year on implementing the so-called Ecophyto plan. In this paper, we evaluate the success of this program, focusing on its flagship scheme, which has provided technical assistance to 3,000 volunteer pilot farms since 2011. To do so, we use panel data collected from a representative sample of vineyards: the agricultural systems known as the largest users of pesticides. We use a slate of quasi-experimental approaches to estimate the impact of participation in the program on pesticide use and crop yields on enrolled vineyards. We find that participants have achieved reductions in pesticide use that ranges from 8 to 22 percent, thanks to the program. We moreover find that the reduction in the use of chemicals was accompanied by an increase in the use of biocontrol products. Finally, we find that this change of practices resulted in a reduction in yields for a fraction of enrolled farms while others seems to have maintained yields. Although below the expectations of the French government, these results seem rather encouraging, as they suggest that technical assistance alone can be effective in reducing significantly pesticide use in the agricultural sector.