This paper tackles several issues under-studied concerning agri-environmental schemes (AES), namely requirements related to ecological focus areas (EFA) and collective participation. For this purpose, choice experiment was used to assess farmers’ preferences towards AES in olive growing of Southern Spain. A high heterogeneity was found, being identified four different classes of farmers, from potential participants to intermediate and non-participants. Almost half of the farmers would implement EFA at low monetary incentives (€8-9/ha per 1%-EFA) and the rest would do it at moderate to high monetary incentives (€41-151/ha per 1%-EFA). Most of farmers would not participate collectively with an up-to-30% bonus.