This paper argues that the need for a core -fourth pillar‖ of sustainability/sustainable development, as demanded in multiple arenas, can no longer be ignored on the grounds of intangibility. Different approaches to this vital but missing pillar (cultural-aesthetic, religious-spiritual, and political-institutional) find common ground in the area of ethical values. While values and aspects based on them are widely assumed to be intangible and immeasurable, we illustrate that it is possible to

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... rationalize them in terms of measurable indicators when they are intersubjectively conceptualized within clearly defined practical contexts. The processes require contextual localization of items, which can nonetheless fit into a generalizable framework. This allows useful measurements to be made, and removes OPEN ACCESS Sustainability 2013, 5 3036 barriers to studying, tracking, comparing, evaluating and correlating values-related dimensions of sustainability. It is advocated that those involved in operationalizing sustainability (especially in the context of creating post-2015 Sustainable Development Goals), should explore the potential for developing indicators to capture some of its less tangible aspects, especially those concerned with ethical values.