In 1972, the US Congress enacted the Clean Water Act (CWA) to protect US water resources. A critical section (305[b]) of the CWA calls for periodic accounting of the success or failure of efforts to protect and restore US waters. Over the years, several groups have reviewed the available data and concluded that they do not adequately describe the condition of US waters. The Wadeable Streams Assessment presents the first set of results from what will be a long-term partnership between the US Environmental Protection Agency, the individual states, tribal nations, and other federal agencies. The goal of this partnership is to fill critical information gaps that remain a deterrent to our ability to determine whether our policies and investments have resulted in improvement of US water resources.