Stakeholders of the Poitou-Charentes region (central western France) worked together to analyse the environmental impacts of regional dairy chains so as to identify improvement options. We analysed fifteen dairy farms of the pays Thouarsais using life cycle analysis. Results for post-farm dairy chains are based on data for several dairy plants in Poitou-Charentes, which process cow and goat milk into butter, soft white cheese and traditional goat cheese. The ongoing analysis of dairy systems enlightened the necessity to take into account the multifonctionality of agriculture to compare different situations and to identify the best practices. Obviously agricultural activities generate flows of biomass and energy linked with farming processes and ecosystems. But in the other hand, they provide products and services, including non trade concerns. A new challenge for LCA consists in making clear if advantages and disadvantages are evenly balanced. For this purpose, the authors propose an integrated approach which opens a new perspective for environmental strategies in supply chains.