Starting from the problem of supply chain’s effectiveness dependency on good coordination of participants, this paper builds a theoretical and methodological tool for studying the quality of communication between parties in the process. The aim of the study, qualitative and explorative in its nature, was twofold. First, beer game simulation was used on students, to demonstrate the bullwhip effect, and to enable them learning from their own experience not only economical but also psychological effects of lack of cooperation. Second, there was an idea to analyze communication of parties in supply chain by observing interaction and interviewing participants and then categorizing their communication using a transactional analysis terminology as a system of classification. The hypothesis that transactional analysis can be used as a theoretical framework and methodological procedure for diagnosing and understanding social interactions was explored. As the study revealed some patterns, well described by transactional analysis concepts, psychological theory has a potential to improve understanding and practical realization of supply chain coordination and to provide some suggestions for overcoming communicational problems in supply chains of future managers.