This study sought to identify and examine current policies and strategies for controlling prison gangs and to determine the ways in which correctional facilities were dealing with gangs in their institutions. Respondents to the mail survey included 55 local jail systems and 52 state prison systems (the 50 state Departments of Corrections, the District of Columbia, and the Federal Bureau of Prisons). The survey question text used the term "security threat group" (STG), which was defined as "two or more inmates, acting together, who pose a threat to the security or safety of staff/inmates and/or are disruptive to programs and/or to the orderly management of the facility/system," rather than the generic term "gang." Data contain information on total inmate population, number of STGs, number of inmates identified as confirmed, suspected, associate, and drop-out members of STGs, total incidents of violence, number of violent incidents by STG members, management strategies to deal with gangs, and names of STGs known to be present within the system.