Purpose: This research presents the development of a Building Passport for Sustainable Conservation (BPSC) as a questionnaire with a set of 23 core indicators, for a baseline assessment of heritage buildings. The aim of this tool is to identify priorities for future interventions, by recognising the contributions of heritage buildings to sustainability that should be preserved and the fragilities that need to be improved. Design/methodology/approach: The BPSC uses a selection of core indicators for sustainability observable on heritage buildings. It was applied to four different case studies of modern heritage in the Netherlands, to verify its applicability and limitations. Findings: The results suggest that this tool has the potential to c...