The National Estuarine Research Reserve System is a network of 29 estuarine areas—places where freshwater from the land mixes with saltwater from the sea—established across the nation for long-term research, education, and coastal stewardship. The reserves are a partnership between NOAA and the coastal states and territories. NOAA’s Office for Coastal Management is responsible for administering the reserve system. Each reserve is managed on a day-to-day basis by a lead state agency or university, with input from local partners. The mission of the reserves is to practice and promote coastal and estuarine stewardship through innovative research and education, using a system of protected areas.