This first of four sessions focuses on "Defining the Problem." David Muhlhausen of the U.S. Justice Department's National Institute of Justice (NIJ), the sponsor of the seminar, briefly reviews NIJ's funding support for research that focuses on the causes and treatment of stress, posttraumatic stress disorder (PTSD), and suicide among law enforcement officers, as well as personnel in the broader criminal justice community. Another NIJ representative moderates a panel that facilitates a discussion on stress and trauma and how to deal with it, which includes questions and comments from the audience. Panelists include a retired police officer who spent 24 years mentoring law enforcement officers who had experienced critical incidents; a research professor who has focused on police stress, health, and suicide; an NIJ LEADS Scholar who has addressed officer stress and trauma through "mindfulness" training; and a researcher who has studied resiliency to stress and trauma. Three other videos from this seminar on protection against stress and trauma for law enforcement officers address research and practice, next steps, and audience questions and answers.