Impact of agri-enviromental scheme participacion on dry-land cereal farms’ efficiency This paper analyses farm productive technical efficiency and its relationship with enrolment in an agrienvironmental program in Andalusia (Spain). First, a mono-ouput multi-input production frontier function is estimated for 128 dry-land cereal farms using data envelopment analysis (DEA). The results obtained show high efficiency indexes for all farms (83%). However, scale efficiency is lower (74%) due to the presence of decreasing economies of scale, which leads to medium global efficiency in the agro-ecosystem (59%). When considering the impact of agri-environmental programs, comparing efficiency levels between enrolled and non-enrolled farm a significant difference is found, with lower efficiency indexes found for participating farms. When considering additional factors that can explain efficiency differences, these are reduced although significant negative impacts are still associated with participation in agri-environmental schemes.