Physical representations of data have existed for thousands of years. However, it is only now that advances in digital fabrication, actuated tangible interfaces, and shape-changing displays can support the emerging area of 'Data Physicalization': the study of computer-supported, physical representations of data and their support for cognition, communication, learning, problem solving and decision making. As physical artifacts, data physicalizations can tap more deeply into our perceptual exploration skills than classical computer setups, while their dynamic physicality alleviates some of the main drawbacks of static artifacts by facilitating their crafting, supporting adaptation to different data, and encouraging sharing between different users. The exploration of physicalizations poses a set of unique multi-disciplinary challenges: design, technical implementation, interaction, and evaluation. The primary goal of this workshop is to bring together practitioners from a diverse range of communities to explore the challenges in 'making data physical' and to set a research roadmap for the next years.