The long-term goals of the National Water Quality Assessment (NAWQA) and National Stream Quality Accounting Network (NASQAN) programs are to describe the status and trends in the quality of a large representative part of the Nation's surface-water and groundwater resources and to provide a sound, scientific understanding of the primary factors affecting the quality of these resources. USGS Water Science Center staff provide support to the NASQAN and NAWQA Surface Water Status and Trends Coordinator and NAWQA National Leadership Team and provide guidance to the NAWQA study units on surface-water status and trends activities.