ABSTRACT. Specialised literature on the uptake of agri-environmental schemes (AES) has paid little attention to how this can be influenced by the different types of agricultural systems. This paper analyses the heterogeneity of farmers' preferences towards these schemes, distinguishing between different sub-systems within the same agricultural system. We use the choice experiment method to analyse the case study of three olive grove sub-systems in southern Spain, with the sub-systems ranging from extensive to intensive. The results reveal inter and intra sub-system heterogeneity of farmers' preferences towards AES both in general and specifically related to scheme attributes. A variety of factors appear to lie behind inter sub-system heterogeneity, especially those associated with sub-system specificities (principally, the type of joint production). Likewise, numerous factors play a role in intra sub-system heterogeneity, most of them related to farm/farmer socioeconomic and physical characteristics. These findings will help in the design of more efficient AES.