Food and water are two basic human needs. However, global coverage figures from 2002 indicate that, of every 10 people:
* roughly 5 have a connection to a piped water supply at home (in their dwelling, plot or yard);
* 3 make use of some other sort of improved water supply, such as a protected well or public standpipe;
* 2 are unserved;
* In addition, 4 out of every 10 people live without improved sanitation.

At Earth Summit 2002 governments approved a Plan of Action to:
* Halve by 2015 the proportion of people unable to reach or afford safe drinking water. The Global Water Supply and Sanitation Assessment 2000 Report (GWSSAR) defines “Reasonable access” to water as at least 20 liters per person per day from a source within one kilometer of the user’s home.
* Halve the proportion of people without access to basic sanitation. The GWSSR defines “Basic sanitation” as private or shared but not public disposal systems that separate waste from human contact.

Generally speaking the more developed countries of North America, Europe and Russia will not see a serious threat to water supply by the year 2025, not only because of their relative wealth, but more importantly their populations will be better aligned with available water resources. North Africa, the Middle East, South Africa and northern China will face very severe water shortages due to physical scarcity and a condition of overpopulation relative to their carrying capacity with respect to water supply. Most of South America, Sub-Saharan Africa, Southern China and India will face water supply shortages by 2025; for these latter regions the causes of scarcity will be economic constraints to developing safe drinking water, as well as excessive population growth.