Frequently enabled by digitalization, great transformations are taking place in socio-technical systems such as energy, telecommunications, and mobility. These transformations indicate widespread shifts in societal infrastructure systems, rearranging relations between governments, industries, NGOs, and consumers. In this context, the question of trust in systems - as introduced by sociologists Luhmann, Coleman and Giddens - acquires new urgency, as yet uncommented upon in trust research, or socio-technical systems debates. Focusing on the energy sector, Patrick Sumpf analyzes the meanings of system and trust to develop a framework for both theoretical and empirical research, which is synthesized into an "Architecture of Trust" in systems.