Overview: Crime prevention is necessary in any society. Without it, crime would continue to skyrocket and the society as a whole would suffer. This special volume of The Annals, What Works in Preventing Crime? Systematic Reviews of Experimental and Quasi-Experimental Research, originated with the 2001 Jerry Lee Crime Prevention Symposium. This 2-day conference focused on systematic reviews of criminological interventions. From there, many articles were put together discussing the methods of conducting systematic reviews, research findings from prevention and intervention studies, and what this means for the future of crime prevention. This special volume of The Annals also focuses on the Campbell Collaboration and its Crime and Justice Group. It is set up to prepare, maintain, and disseminate evidence-based research in crime and make it available electronically to the general public. This is an important organization, and its findings make it easier for the general public as well as policy makers to see where things need to be changed in order to continue preventing crime that would have happened without the prevention programs in place.