The water sector was designated by President Bill Clinton's 1998 Decision Directive (PDD) 63 and President George W. Bush's 2001 Executive Order (EO) 13231 as one of eight critical infrastructure sectors deemed essential to the nation's wellbeing. A key objective of PDD 63 and EO 13231 was the establishment of Information Sharing and Analysis Centers to improve security by facilitating the sharing of information. Additionally, Homeland Security Presidential Directive (HSPD-7) encouraged the creation of private sector information sharing and analysis mechanisms, such as the WaterISAC, to protect drinking water and wastewater infrastructure from attack. In 2001, the Association of Metropolitan Water Agencies (AMWA) was selected as the official liaison between the water sector and the federal government and immediately established the WaterISAC with a grant from the US Environmental Protection Agency. The WaterISAC's development has relied on advisory groups that include individual utility subscribers and representatives of the AMWA, the National Association of Clean Water Agencies, the National Association of Water Companies, the American Water Works Association Research Foundation, the Association of State Drinking Water Administrators, the National Rural Water Association and the American Water Works Association.