The primary objective of this research was to thoroughly assess the social, economic, and environmental sustainability of 10 peasant farming production systems linked to Peasant Markets by means of economic, monetary and energy balances, and social analysis. Semistructured interview techniques were employed for data collection during the year 2011. Only three farming production systems—El Colegio, Villarrica, and Tuta—were comprehensively sustainable. In sum, peasant valuation of social and environmental benefits, agroecology, family labor, food self-sufficiency, short food supply chains, market linkage, collective cooperation, peasant pluriactivity, and food processing were all related to the strong sustainability of the peasant economy.