Opening remarks by Beth McGarry, Deputy Assistant Attorney General of the U.S. Justice Department's Office of Justice Programs (OJP), reviews the National Institute of Justice's (NIJ's) research projects that are giving law enforcement agencies the tools they need to protect their communities from gun violence. They emphasize partnerships with researchers in order to produce a reliable understanding of the problem and the strategies that are most likely to yield positive, sustainable results. The panel presentations in this video report on what works, based on NIJ-funded research. David Hemenway, a professor at the Harvard School of Public Health and Director of the Harvard Injury Control Research Center, provides an overview of firearms injuries. Charles Wellford, a Professor Emeritus of Criminology and Criminal Justice at the University of Maryland, reports on a project that involves the Prince George's County Police Department (Maryland) in reducing gun violence. Susan Sorenson, who works at the University of Pennsylvania in the public health field of family and sexual violence, reports on her work regarding firearms and domestic violence. Hank Sawinski, Chief of Police of the Prince George's County Police Department (Maryland) discusses research presentations and their relevance to the work of the police department.