RESUMO
Milk production is an important economic and social activity in Brazil. Failure to meet institutional and market demands for quality and sustainability has led farmers, particularly small-scale farmers, to leave agriculture. The aim of this study was to assess and compare the sustainability of dairy farms in Paraná, Brazil. A semi-structured questionnaire was administered to 75 dairy farm operators. Sustainability indicators were generated on the basis of economic, environmental and social data using exploratory factor analysis. Factor scores were subjected to hierarchical clustering, which resulted in the formation of three groups of dairy farms. Groups 1, 2 and 3 had high, intermediate and low levels of sustainability, respectively. Group 1 comprised large-scale dairy farms with high productivity. Dairy farms with intermediate sustainability (group 2) had medium production capacity, and farms with low sustainability (group 1) had the smallest production scale and capacity. Large-scale dairy farms have greater economic, environmental and social sustainability and are, therefore, more likely to survive in the medium and long term.