The Livestock Farming System (LFS) concept was developed to assess and model the interactions between the human and biotechnical dimensions of livestock husbandry activities. We recall the origin and the fundamentals of these integrated approaches in animal production, and their applications at the livestock production unit level, for assessing the relationships between farmer's management decisionspractices and herd performances. We illustrate how the concept evolves with the changes in livestock farming, due to the farmers' new expectations for work that is under control and with the society's demands for environmentally friendly agriculture. The LFS approaches are now engaged in a deep renewal in order to adapt the framework to the Sustainable Development issues: what is at stake is to analyse the adaptive capacities of socio-ecological systems at the territorial level.