Changes affecting livestock farming systems have made labour a central concern for both the sector and the farmers. The challenge lies in increasing labour productivity to improve work conditions. Farmers voice new work expectations particularly a demand to separate their private lives from their work as controlling working hours and being able to have free weekends and holidays. In order to provide viable livestock farming systems, work productivity and work flexibility can be analysed together. A work organization survey was carried on 15 organic sheep farms in the Massif Central region in France. The sample was characterized by different reproductions rhythms (one to three lambings/year). Routine work (work to be done every day) varied from 78 to 4343 hours/year. This variability can be explained by the number of workers, the sheep breeding and the level of equipment. 96 % of the routine work was carried out by farmers themselves. Only one farmer employed a permanent wage earner. The efficiency of the routine work was also diverse (1 to 7,8 hours/ewe/y). It was better in large herds. The calculated time available (room for manoeuvre in time) varied from 454 to 1199 hours/farm/year. Three annual distribution of the calculated time available were identified according to the reproduction rhythm of the herd (periods of lambing) and the work with the forage area (silage, hay making). Adaptive capacities were assessed by adjustments of forms of work organization. The results highlighted diverse adaptive capacities: the stability or the constant adjustments over the year to diverse events (climatic, workforce, livestock management, etc.). The reproduction rhythm can be a lever of work flexibility for farmers. Other factors are also important: other activities on the farm (transformation, direct selling, etc.), workforce composition and level of equipment. These results could help research and development organizations to design farming systems that are better aligned to the quality-of-life expectations voiced by farmers.