This lecture examines the definition and technical challenges to sustainable water. Cohen looks at water quantity, distribution and efficiency to better understand the issues water supply. He examines the evolving technologies of water as well as briefly touching on issues of ocean quality. Cohen also discusses the issue in the context of organizational and management challenges, financial challenges, and the public policy. Content in this video is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. http://creativecommons.org/licenses/by-nc-nd/3.0/