Complex societal challenges inherently transcend disciplines and can only be addressed through interdisciplinary approaches. In order to equip (future) professionals to engage in interdisciplinary research, they therefore need to develop competencies for interdisciplinary knowledge integration. In this presentation we will outline our action research project in the context of a novel, innovative interdisciplinary master course. We follow master students during interdisciplinary teamwork, in order to study how they develop competencies for interdisciplinary knowledge integration. We divide the competencies into two categories: epistemic steadiness (ES) comprises the competencies that are required to contribute one’s own knowledge base to an interdisciplinary effort and epistemic adaptability (EA) comprises the competencies that are required to engage with the knowledge bases of other collaborators in the interdisciplinary effort. Throughout the project we assessed the students’ individual competencies, as well as integrative capacity on team level. We designed and implemented training activities (e.g. discussion formats, reflection exercises and team dynamics interventions) to facilitate knowledge integration, specifically targeting the development of ES and EA. In this presentation we tell the story of how these teams as well as the individual competencies developed and how training activities shaped the process of interdisciplinary knowledge integration.