In the aerospace industry, systems engineering practices have been exercised for years, as a way to turn high-level design objectives into concrete targets on system functionality (e.g. range, noise, and reliability). More difficult is to decompose and clarify sustainability implications in the same way and to compare them against performance-related capabilities already during preliminary design. This article addresses the problem of bringing the important—yet typically high level and complex—sustainability aspects into engineering practices. It proposes a novel integrated model-based method that provides a consistent way of addressing the well-known lack of generic and integrated ways of clarifying both cost and value consequences of sustainability in early phases. It further presents the development and implementation of such approach in two separate case studies conducted in collaboration with a major aero-engine sub-system manufacturer. The first case concerns the assessment of alternative business configurations to maintain scarce materials in closed loops, while the second one concerns the production technology of an aero-engine component. Eventually, this article highlights the learning generated by the development and implementation of these approaches and discusses opportunities for further development of model-based support.