This Ph.D. thesis focuses on smart product-service systems (PSS) engineering, aiming to integrate service and digital infrastructure development processes while connecting related products and organizational units. A methodology developed through the CASE Research Cycle facilitates this integration, intended for PSS development projects across various stages, including business model analysis, conceptual design, detailed service and infrastructure design, and validation/testing. The methodology operates on two levels. The macro-level addresses the overall development process, PSS typology, and an enterprise-wide IT landscape supporting the system's lifecycle. Its objectives include fostering stakeholder understanding, establishing a conceptual model for PSS, and guiding the development process. This level features a process model, a typological PSS model, and an IT architecture concept, extending the VPE-SDM methodology for cybertronic system development. Conversely, the micro-level focuses on designing services and digital support infrastructure, defining connections to product development processes. It includes a system analysis and design synthesis process, an ontology-based concept, and a meta-model for representation in the Systems Modeling Language (OMG SysML), along with prototypical integrations for modeling support in commercial tools. Design verification and validation are enhanced through the formalism of SysML m
