Agenda 21 indicates that methodologies and instruments should be developed in order to identify areas where sustainability is, or may be, threatened by the environmental effects of demographic trends and factors. Both current and projected demographic data linked to natural environmental processes would be incorporated and hazardous areas that are most vulnerable to erosion, floods, landslides, earthquakes, snow avalanches and other natural hazards would be identified.
This strategy features in the framework of Agenda 21 as formulated at UNCED (Rio de Janeiro, 1992), now coordinated by the United Nations Commission on Sustainable Development and implemented through national and local authorities.