In 1999, the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) and the Federal Bureau of Investigation (FBI) selected IBIS as the standard ballistics imaging technology for their then-proposed National Integrated Ballistics Information Network (NIBIN). Implemented in 2000, NIBIN aims to unify and coordinate Federal, State, and local law enforcement efforts in using ballistics technology to analyze and match recovered gun crime evidence within a jurisdiction and across different jurisdictions. This paper focuses on the use of ballistics imaging technology by the Boston Police Department's (BPD's) Ballistics Unit. In March 1995, Boston was one of the first major cities to receive the IBIS technology. The system was fully implemented when the BPD Ballistics Unit made its first IBIS match in July 1995. Prior to the adoption of IBIS, BPD ballistic operations typically consisted of manually matched bullets and cartridge casings recovered at a crime scene to determine whether the bullets or casings were fired from a suspect's firearm. Since adopting the ballistics imaging technology, the BPD test fires all recovered crime guns, and the expended bullets and cartridge casings are imaged and entered into the IBIS database. Only noncrime guns that are held by the BPD for safekeeping are not imaged. As of December 2003, the Ballistics Unit had entered some 2,400 bullets and 12,700 cartridge casings into its imaging database. A total of 396 IBIS-related matches have been recorded. To determine whether the adoption of the IBIS technology was associated with a change in productivity, this study examined the annual and monthly number of cold hits made by the Ballistics Unit for the 13 years between 1990 and 2002. Using negative binomial regression models to analyze time series data on ballistics matches, the study found that ballistics imaging technology was associated with a more than sixfold increase in the monthly number of ballistics matches. Cost-effectiveness estimates and qualitative evidence also indicate that ballistics imaging technology allows law enforcement agencies to make matches that would not have been possible with traditional ballistics methods. 2 figures, 2 tables, and 16 references