This chapter on global water resources is a companion to Chapter 9, which dealt with water resources in the United States. This chapter addresses all potentially useful sources of water on the planet to support the human endeavor (i.e., agriculture, industry, municipalities, and to support ecological function). This topic is addressed through the topics of the history of global water resources, current global water resources, general global water resource issues, and human health issues related to global water resources. An application section provides three Illustrative Examples related to global water resources and water resource management issues.