Pasture-based livestock systems are a key element for the maintenance of the dehesa ecosystem. However, adaptative changes (mainly intensification) are reducing their sustainability. As consequence, sustainable livestock systems must be found and implemented. Due to this, this work assesses the sustainability of 63 beef cattle farms (including organic and conventional ones) with two aims: (i) to identify the most sustainable systems and; (ii) to establish management measures in order to increase farms? sustainability. For this purpose, a methodological adaptation of the MESMIS Framework was applied. A cluster analysis allowed us to identify three farms typologies. Typology 1 (organic farms) had the highest scores for the sustainability index (66.75%) and for the majority of blocks of action. However, changes aimed at improving their self-reliance must be introduced. Typology 2 (mainly conventional) showed the lowest sustainability scores (52.44%), especially with regard to the agro-ecosystem and herd management. Due to this, this typology should implement agricultural practices more environmentally friendly, as well as a herd management based on preventive medicine. However, they showed adequate levels of productivity and competitiveness. Typology 3 (mixed) also showed low sustainability scores (53.41%). Its level of self-reliance is high. However, its low productivity and competitiveness must be encouraged. In general terms, all typologies are required to improve their agro-ecosystem management, to increase their competitiveness and business agility, as well as to reduce their economic risk. These aims can be achieved by means of fattening their calves, increasing the business diversification, elaborating products by the producer, and direct sales.