This paper aims at exploring what is covered by « adapting to last » with a farming systems approach. Long term dynamics can be analysed as adaptive cycles, the system being permanently exposed to disturbances and shocks. Mobilizing the concept of resilience, we analyse the factors that differentiate the principles for long term action the livestock farmers have, principles which give consistency to the family - farms trajectories. With the concept of operational flexibilty, we qualify the sources of flexibility the livestock farmers maintain to cope with hazards. They are internal, related to the production process regulation properties, to the technical (adaptive or rigid) specifications, to the sales policies, or external related to the information and commercial networks. Understanding the production process regulation properties require livestock farming systems models (i.e. combining decisional and biological sub-systems) that can simulate how herd dynamics operate under fluctuant rules or productive parameters. It also require to evaluate the room for manoeuvre the work organization let to the farmer. All these aspects are illsutrated with on farm studies in herbivore systems (sheep, dairy, beef).
adaptation; flexibility; livestock farming systems; resilience; room for manoeuvre; system regulations
