Editors' Summary: On September 19, 2007, the Environmental Law Institute hosted a seminar to examine developments in environmental standing in the U.S. Court of Appeals for the District of Columbia Circuit following the Supreme Court's decision last term in Massachusetts v. EPA. The panelists discussed the concept of a risk-based standard for proving "injury-in-fact" in environmental and public safety cases in light of such recent decisions as NRDC v. EPA I and II and Public Citizen v. NHTSA. The seminar concluded with a question-and-answer period. Below is a transcript of the event. [Transcribed by ACE Transcription Service, Washington, D.C. The transcript has been lightly edited, and citations have been added, for ease of reading.]