Agriculture is the main land use and one of the main drivers of biodiversity loss. In particular, intensive farming practices have contributed to biodiversity loss, which is why many governments have implemented agri-environmental schemes (AES). Farmer collaboration at landscape level is important to achieve effective AES. The Dutch government opted for such an approach and decided that only farmer collectives were entitled to take part in AES. In this paper, we evaluate 36 Dutch farmer collectives. Through the lens of professionalisation, we investigated which characteristics of professionalisation enable farmer collectives to work towards an effective AES in terms of collaboration at landscape level. We used spatial concentration of conservation measures as a measurement of an effective AES and, based on expert judgement, selected five characteristics of professionalisation that directly impact AES effectiveness. We applied a fuzzy-set Qualitative Comparative Analysis (fsQCA) in order to explore which of these characteristics singly or in combination contribute most to spatial concentration. We found that different combinations of characteristics of professionalisation enable farmer collectives to work towards spatial concentration. First, we found that working on the maintenance and development of qualifications of participants is for most farmer collectives important to work on more spatial concentration. Second, the combination of having a strategy for agrobiodiversity in combination with working on the qualifications of the field workers is important. And when the network capability or the presence and use of enabling systems are missing, the qualifications of the field workers is important. Based on our findings, we conclude that the qualifications of participants and fieldworkers (i.e., regional coordinator, ecologist and field officer) are the most important characteristics of professionalisation to contribute to spatial concentration at the moment.