BWCs have spread rapidly across the United States. In 2013, about one-third of U.S. municipal police departments had implemented BWCs. The general public has also embraced police use of BWCs. Current research on the impact of BWCs suggests that they may have benefits for law enforcement; however, additional research is needed to provide a fuller understanding of their impact on policing. Proponents of BWCs believe they can provide more transparency and accountability in police interactions with members of the public, thus improving police-community relations. BWCs are also envisioned by proponents as improving the documentation of officer-involved events. BWCs are also expected to improve citizen responses to police. In addition, BWCs are viewed by proponents as a means of improving police training by providing documented case studies of how police should or should not act under various types of scenarios in police interactions with members of the public or criminal suspects. In 2014, researchers at Arizona State University found that officers equipped with BWCs were more productive in making arrests, had fewer complaints against them compared to officers without BWCs, and had higher numbers of citizen complaints resolved in their favor. Another study conducted with the Rialto (California) Police Department found similar decreases in citizen complaints lodged against officers with BWCs, along with decreases in use-of-force incidents. Officers with BWCs were also found to be more cautious in their actions and sensitive to possible scrutiny of video footage by their superiors. This article discusses research methods for conducting evaluations of the impact of police use of BWCs, which must keep pace with their increasing use.