The aim of this work is to assess the flexibility of production allowed by the extensive conditions of production faced with variations in the environment (market variations and climate fluctuations) of the Limousine beef systems. The study used a case-based methodology in which seven beef farms with less than 1 LU/ha were chosen. Data collection was based on three interviews using a semi-structured questionnaire and on the analysis of the productive and economic results for a 15-year period (1991-2005). The main evolution of these farms is related to an increase in work productivity associated with an increase in herd size. Herd increase was made possible by enlarging the area, the margin of intensification being limited in these regions. To take advantage of the enlarged land area, females were reared for fattening or for reproduction instead of selling them at weaning. The Limousin female provides a wide product mix because of its plasticity, as has been studied by several researchers. This diversification and capacity for adaptation from one product to another is the mix flexibility. This mix flexibility is achieved by delaying product differentiation; it is a form of production flexibility that can reduce the risk of under-producing or over-producing through varied product configurations. Calves sold to the Italian market after weaning are generic products, associated with a flexible production process to overcome fluctuations in forage availability due to climate variations. The introduction of maize silage for feeding acts as an alternative route (actual and potential) through the system to overcome unexpected forage shortage from natural grasslands as a result of droughts. The study shows that extensive farming systems have developed types of flexibility to match different factors of uncertainty from the environment. An important challenge for further research on flexibility is to develop knowledge regarding the relationship between time and extent of change