EPA is directed by the Safe Drinking Water Act (SDWA) to annually report on Public Water System (PWS) compliance in the United States. To meet this requirement, EPAs Office of Enforcement and Compliance Assurance (OECA) publishes the National Public Water Systems Compliance Report (Report). The Report for 2009 documents that, while the majority of the U.S. population served by PWSs receives safe drinking water, many systems incurred significant violations of Federal drinking water quality standards. Additionally, EPA and primacy agencies need to work together to improve data quality, which affects EPAs ability to accurately calculate the extent of noncompliance. EPAs new Enforcement Response Policy (ERP) issued on December 8, 2009, establishes a water system-based approach to defining, prioritizing, and addressing noncompliance with Federal requirements. The ERP is expected to be instrumental in improving compliance trends. In 2009, there were 153,399 public water systems in the U.S., serving over 300 million users. Small systems comprise the vast majority of all systems. Noncompliance occurs more frequently at smaller systems often because they may have fewer resources to operate and maintain compliance. For this reason, EPA, states, and other organizations provide significant resources to small water systems to build their capacity to properly finance, operate, and maintain their drinking water systems. Among other mechanisms to support small systems, EPA funds third-party technical assistance providers and eight university-based technology assistance centers, conducts on-site visits and maintains multiple, free online financial and technical websites.