The mission of the Security Threat Groups (STG) Unit is to effectively validate STG related persons, gather intelligence on STG related criminal activities, and provide investigative support in all STG re-lated occurrences. The STG Unit is tasked with maintaining and supervising the department’s STG program, which as of 2017 consists of 12,444 validated inmates in 315 different gangs. The STG Unit is a part of the SIS. The STG Unit maintains working relationships with the Georgia Gang Investigator Association (GGIA) and GISAC. The STG Unit is often called upon as subject matter experts and con-ducts quarterly statewide training.