In the last 20 years, the paradigm of sustainability has experienced an incomparable success. However, many environmental problems have become even more urgent. This book identifies a lack of appropriate indicators of sustainability as one key hurdle to implement the abstract and intangible paradigm. Therefore, different indicators of sustainability (e.g. the Ecological Footprint, monetary valuation, sets of indicators) are introduced and evaluated. Based on their main benefits and shortcomings, criteria and guidelines for measuring sustainability are developed. In order to meet these criteria, the author chooses an interdisciplinary approach and suggests integrating environmental space as a non-monetary numeraire into the economic framework of measuring sustainability. Finally, different indicators are applied on a national and global scale to empirically compare and analyze the drivers underlying (un)sustainable development.