## 1 Introduction  
The achievement of global agricultural sustainability necessitates the engagement of farmers through the constant modernization of their farms, the adoption of more efficient farming practices being supported by innovative technologies, and the improvement of their productivity [1]. The interrelationship between improvement of production practices and policy instruments, as a means of technology transfer, is proven to be quite strong and effective [2]. The implementation of policies' guidelines by the farmers is constrained by various personal, socioeconomic, geographical, demographic, political, and technological factors [3]. Among the most important means for helping farmers to adopt more sustainable farming practices, is their knowledge capacity around the multiple issues that they are faced with when planning and managing their holdings [4]. The benefits of education and knowledge at the farm level are then translated to significant productivity and income gains of the agricultural sector as a whole [5]. Farmers acquire knowledge through informal and formal channels [6]. The first category includes information flows through social interactions, both physical and digital (social media), as well as the collection of information by reading of resources such as books, journals, and websites. In the latter category, the most important sources are the enrollment in educational programs, the Extension Services (ES), and the involvement in Participatory Research Projects (PRP) [4]. Such cooperation requires the formation of a consortium consisting of research institutes and market oriented stakeholders, working together for the resolution of specific problems related to the value chain of products. These kinds of projects can either be co-financed on a national or EU basis, or be fully financed by the private sector or cooperatives. Indicative example is the CROPFEED project, co-financed by the Greek General Secretariat of Research and Technology ([[http://cropfeed.agr.uth.gr](http://cropfeed.agr.uth.gr)]([http://cropfeed.agr.uth.gr](http://cropfeed.agr.uth.gr))). In this project locally produced leguminous crops are being fed to milking cows, aiming to decrease the high dependency of imported GMO soya. Similar rationale follows the Bio-circular project, co-financed by the same authority. The most important formal source of information, especially in developing countries, is this of ES which come up with various settings and objectives across the different parts of the globe. The effectiveness of these kinds of programs still remains under a heavy critique. This is because, despite the documented changes that such projects have brought in several countries [5], many authors believe that their impact would be even greater if they were designated in a more farmer-centered context, lying away from the top-down unidirectional approach that many ES have adopted in the past [7; 8]. The need for more farmers' engaging type of extensions projects has led to the development of the so-called Participatory Extension Programs (PEP) which are taking the form of meetings over a predefined period of time, typically 1-3 years and whose targets and objectives are commonly agreed by farmers and researchers [9]. On the other side, PRP could be regarded as similar to the PEP ones, with the exception that they overemphasize the role of experiments and field tests over the soft transferring activities of knowledge and best practices. The projects call for the active participation of farmers toward the joint development of technological and innovative solutions to common challenges and their constant involvement over a rather large period of time [10]. This kind of interaction is considered as an integral part of the more general Farming Systems Research approach which seeks to study in depth all the social, economic, environmental, and governance dimensions of rural life [11].