This article takes a critical look at the evaluation implementing measure within 10 French schools changing school climate and bullying among peers. During 26 months the teachers and staff have been trained to improve communication teacher / staff / students. The aim was to measure the impact of training on the school climate by taking into account the situation of each institution at T0, T1 and T2. If the evaluation reveals a transformation of the ways of being and to observing improving school climate, it has its own limitations, which must be taken into account to modulate the comments and analysis.