ABSTRACT
To guide policymaking we select indicators and set thresholds at the national level. For each of the six key sustainable themes defined in our book we make a thorough examination and comparison of potential indicators. We select the one that best reflects the key theme and its theoretical foundation and for which high-quality data are widely available. The corresponding threshold reflects a minimum (or maximum) acceptance level. Thus, it does not represent a goal, but rather a threshold we must respect to avoid unacceptable, irreversible, and/or uncertain consequences. The six thresholds form the sustainable development space.
