There are 93 U.S. Attorney offices located throughout the United States, Puerto Rico, the U.S. Virgin Islands, Guam, and the Northern Mariana Islands. One U.S. Attorney is assigned to each of the judicial districts, with the exception of Guam and the Northern Mariana Islands where a single U.S. Attorney serves both districts. Each U.S. Attorney is the chief federal law enforcement officer within his or her particular jurisdiction, acting under the guidance of the "United States Attorneys' Manual". They supervise district offices with as many as 350 Assistant U.S. Attorneys (AUSAs) and as many as 350 support personnel.