In the context of sustainable development of European post-industrial cities, urban wastelands offer an important potential of surfaces to recapture. The regeneration of these sites is indeed an opportunity to simultaneously create density within the existing built fabric and revitalize some portions of cities and metropolitan areas. Although the launching of several initiatives of this type can be observed, their implication toward sustainable development is in most cases implicit and superficial. In point of fact, integration of sustainability into urban wasteland regeneration projects cannot be summarized by a mere density issue. It requires a proactive search for global quality, implemented in a participative way into the project dynamics, and a continuous monitoring of environmental, social and economic dimensions adapted to such projects. Specifically addressing these considerations, this paper introduces the development of an operational indicator system for the integration of sustainability into the design process of urban wasteland regeneration projects. It aims to provide a tool for structured and continuous evaluation, hinged on their specific characteristics, and to give useful basis to stakeholders involved in their management. Subsequently, the paper presents a first test application performed on a project underway in Switzerland, which validates its usability. Further work suggests the integration of the system into a digital monitoring tool in order to make it applicable to a variety of projects of this type.