Starting with the earlier work of Don Ihde, postphenomenological studies in philosophy of technology have been documenting the many ways in which technologies shape human beings’ relationship to the world. More recently, Material Engagement Theory (MET), originating from cognitive archaeology, ofers descriptions of how human thinking and capacities have been shaped through creative material engagements with the world. Based on a recent collaboration by Ihde and Malafouris (2018), this study applies the joint framework of postphenomenology and MET to design research in light of the rising interest in design literature into relational ontologies and embodied practices. The study is built on data from seven case studies of practices in creative engagement with materials and tools, three out of which are reviewed in depth, namely: felt making, make-up, studio camera operation. The cases are analyzed through the joint theoretical lens to identify and describe the human-thing relations as observed in design. We describe such relations as creative and exploratory, materially and socially relational, reciprocally mediated, situated, embodied, and skilled. Our emphasis is on the first three of these six characteristics, emphasizing relationality, reciprocal mediation, and creativity in engagement, as signifcant contributions of the joint framework to understanding design, making and use in design research. Our conclusion includes a discussion of future research opportunities for studies based on the joint framework.