Description:The paper is investigating the electronic-based traceability systems (ETsystems) that are considered as a valuable tool for the assurance of food safety and quality, for guaranteeing value added to products and ultimately, for serving the transparency and sustainability of agri-food chains. The objective of this research is to investigate the factors influencing the acceptance and use of ETsystems in agri-food chains. A model that identifies the most significant factors influencing farmers' and processors' behavior regarding the installation and operation of an ETsystem is proposed. The theoretical approach is based on a combination of the Technology Acceptance Model 2 (TAM2) and the Theory of Planned Behavior (TPB). The theoretical concept and related hypotheses are tested by means of PLS-SEM analysis of data from the dairy supply chain in Greece. ‘Perceived Control’ and most importantly, the ‘perceived costs’ over the installation and operation of the ETsystem, is the most important factor with the strongest direct effect influencing the intention to install and operate such a system. This effect is stronger in the case of dairy farmers than in the case of dairy processors. Stronger for dairy farmers is also the identification mechanism thus, their need to comply with their social/business group expectations. Useful findings offered for policy makers and regulators interested in the way traceability systems could be successfully integrated within an agri-food sector to guarantee its added value. The limitation of voluntariness and the enforcement of certain mandatory requirements is one tool to exploit and, based on our study, would be more effective at the processors' level.