The American Chemical Society (ACS) National Meeting and Expo:  Chemistry and Water will be held August 25-29, 2019, in San Diego, California.  On August 25, 2019, “Tiny Solutions to Big Problems:  Water Sustainability through Nanotechnology” will be held in support of the National Nanotechnology Initiative’s (NNI) Water Sustainability through Nanotechnology Signature Initiative (Water NSI).  The session will feature an overview of the Water NSI, as well as technical presentations on three specific areas where nanotechnology is being applied:  water treatment, water delivery and use, and water monitoring.  Presentations will be followed by a panel discussion on current challenges and future directions for the nanotechnology community in addressing global water issues.