A wealth of indicators and indicator sets, structured in the form of standards (e.g., ISO, OECD, SDG Index, etc.), have been developed and proposed over the past decades to define and measure urban sustainability. Unfortunately, literature studies confirm that there is a lack of knowledge systematisation for such indicator sets in the sustainability assessment domain. In this chapter, we present and describe a formal representation of knowledge about sustainability indicators and their interrelationships, through the development of a domain ontology. To increase the potential for its adaptability and reuse, as well as to facilitate its continuous redevelopment, we make the developed ontology available online, through a dedicated web portal.@en

In this paper we compare 10 established frameworks for analyzing social-ecological systems. We limited ourselves to frameworks that were explicitly designed to be used by a wider community of researchers and practitioners. Although all these frameworks seem to have emerged from the need for concepts that permit structured, interdisciplinary reasoning about complex problems in social-ecological systems, they differ significantly with respect to contextual and structural criteria, such as conceptualization of the ecological and social systems and their interrelation. It appears that three main criteria suffice to produce a classification of frameworks that may be used as a decision tree when choosing a framework for analysis. These criteria are (i) whether a framework conceptualizes the relationship between the social and ecological systems as being uni- or bidirectional; (ii) whether it takes an anthropocentric or an ecocentric perspective on the ecological system; and (iii) whether it is an action-oriented or an analysis-oriented framework.@en