Water problems exist in all parts of the United States. Furthermore, the problems are becoming more acute and widespread as population and industry grow. The need is pressing for wider appreciation of the nature of water problems. This requires a background of basic facts about the occurrence of water, its quantity and quality, and the manner in which it is used. This report records some of these basic facts. The facts are that the United States as a whole is well endowed with water. Many water problems (which exist in our country) are caused, however,by poor distribution of water in time and place. Because the nationwide supply of water is large, any given locality could be supplied with water sufficient in quantity and suitable in quality, provided that those who need the water can pay the cost. For the most part, then, water problems are basically social and economic. While management is needed, both locally and regionally, with flexibility to respond to broad geographic patterns of economic and social development.