Sustainable development is a normative concept used to prescribe and evaluate changes in living conditions. Such changes are to be guided by four Brundtland aspirations:

1. To satisfy basic human needs and reasonable standards of welfare for all living beings. (Development)

2. To achieve more equitable standards of living both within and among global populations. (Development)

3. To be pursued with great caution as to their actual or potential disruption of biodiversity and the regenerative capacity of nature, both locally and globally. (Sustainability)

4. To be achieved without undermining the possibility for future generations to attain similar standards of living and similar or improved standards of equity. (Sustainability)