Rolando V. del Carmen was, at the time of his death, Distinguished Professor of Criminal Justice (Law) in the College of Criminal Justice, Sam Houston State University. He authored numerous books and articles in various areas of law related to criminal justice. He won all three major awards given by the Academy of Criminal Justice Sciences, taught numerous graduate and undergraduate classes in law, and was a mentor and friend to many of his students. Jeffery T. Walker is Designated University Professor and Endowed Chair of Communities and Crime at the University of Alabama, Birmingham. He has written 10 books and over 100 journal articles and book chapters. He has been involved in almost $300 million in grants from the Department of Justice, National Institutes of Health, National Science Foundation, Center for Disease Control, and others. His areas of interest are social/environmental factors of neighborhoods, legal issues of policing, and crime mapping/crime analysis. He is a past president of the Academy of Criminal Justice Sciences. Editorial experience includes service as Editor of the Journal of Criminal Justice Education. Previous publications include articles in Justice Quarterly, American Journal of Criminal Justice, and Journal of Quantitative Criminology, and the books Legal Guide for Police (Twelfth Edition) and Foundations of Crime Analysis.