摘要：Sustainable development, the great challenge of the twentyfirst century, requires a long-term economic use of valuable, increasingly scarce resources: land, materials, and energy. In Germany, a large share of resources is used for buildings and the related infrastructure; therefore the development of settlements is of crucial relevance in this context. Despite this utilization of resources, questions concerning resource efficiency have predominantly focused on consumer goods. Due to the specific nature of the topic "built environment", we have to consider that the concepts used and the results gained so far are not directly applicable for an analysis of settlement structures. From the perspective of spatial sciences, foundational orientation becomes necessary against this backdrop. This paper systematically introduces basic concepts for resource efficiency, starting with the separate concepts of "resources", "efficiency", and "built environment". Building on these, an integrated concept, "resource efficiency of the built environment", is outlined before some limitations of an efficiency perspective are brought forth. Among several challenges, the criticism of the static nature of classical efficiency concepts stands out. In contrast to efficiency considerations for short-term consumer goods with a defined benefit, in the case of the "built environment" efficiency analyses have to deal with a considerable degree of uncertainty, due to the longer life span of the "product". This especially refers to possibly changing users' expectations and demand preferences. Reflecting on these conceptual restrictions, initial considerations are presented for discussion, outlining to what extent the concept of "resilience" might be suitable for the extension and improvement of an efficiency-driven analysis of the built environment.
