Because of the unpredictability of the markets, of the agricultural policies, and of the climate, farmers need to think of their farming systems’ dynamics in a context of uncertainty about the future. A study was conducted in dairy and beef systems either in France or Uruguay. It aims at characterizing and qualifying the diversity of the paths used to last. The data is based on family–farm trajectories of 35 farms and the analysis framework refers to the adaptive cycle of complex systems by Holling. Three axes of differentiation were established. The first distinguishes action principles guided either by system optimisation or by system flexibility. The second axis opposes “staying small” to “getting bigger to last”. The third axis refers to the diversification of activities and distinguishes i) diversification that helps to preserve the livestock activity from hazards from ii) entrepreneurial diversification with several large agricultural production lines. We discuss the diversity of the paths and their determinants, notably with the consideration of the regional factor. We question what the “assessment of sustainability of livestock farming systems” could mean when considering “the paths to last” constructed by farmers.