The Susquehanna River Basin is a diverse watershed with a multitude of opportunities and an equal array of challenges. Since the earliest days of European settlements to the 21st century, the basin has undergone development from logging, coal mining, and agriculture to urban growth--all leaving their imprint on the landscape and its inhabitants. In recent decades, the quality of the Susquehanna watershed has been transformed in many ways, including an overall improvement in water quality and an engaged citizenry dedicated to protecting the basin's environment. While many challenges remain and new ones will surely surface, it is important to step back and take measure of where the Susquehanna watershed stands today. It is in this context that the Susquehanna River Basin Commission (SRBC), the U.S. Environmental Protection Agency, the Susquehanna River Heartland Coalition for Environmental Studies and Bucknell University partnered to develop the first State of the Susquehanna report. The purpose of the report is to detail the overarching issues in the watershed and provide information on each of them. The seven target issues, referred to as indicators in the report, are: Water Use and Development; Floods and Droughts; Stormwater; Abandoned Mine Drainage; Sediment and Nutrients; Human Health and Drinking Water Protection; and Habitat and Aquatic Resources. These indicators are not meant to be inclusive of the basins threats and opportunities, rather to highlight them as among the key factors influencing the state of the Susquehanna in 2010.