Surfacing design requirements. A conceptual product design framework for entity identification in Smart Product-Service Systems

Smart Product-Service Systems (SPSS) design recognises the need to engage diverse stakeholders, yet traditional design approaches often overlook entities critical in the operationalisation of a SPSS-contextual users, regulators, AI entities-until late implementation stages. This paper argues that entity identification in SPSS design requires interrogating underlying assumptions about which entities matter and why. Drawing from systems thinking and human-centred design, the paper proposes a multi-dimensional framework for reconceptualising entities that warrant design consideration. Rather than presenting a neutral taxonomy, the framework provides structure for examining how design assumptions determine which perspectives are centred and which are overlooked in early-stage design process. Five functional entity categories are proposed, each representing different forms of participation in SPSS and different types of design relevance. The framework nudges designers to reflect critically on entity identification practices, creates a focus on the full ecosystem of entities on whose interdependence SPSS outcomes depend.