Overseas, Diplomatic Security Service special agents are assigned to U.S. diplomatic missions as Regional Security Officers (RSOs). They are responsible for protecting U.S. personnel and their families, facilities, and classified information. The RSO serves as the advisor to the U.S. Ambassador on all security-related matters and implement security programs for dealing with threats posed by terrorists, criminals, and hostile intelligence services.

U.S. diplomatic personnel rely on the RSO to keep them safe overseas. The RSO is the U.S. liaison with the host country’s law enforcement agencies, as well as the primary point of contact for other U.S. agencies needing security information or assistance in that country. The RSO office, also, provide security threat information, briefings and advice to private U.S. businesses and organizations based overseas through the Overseas Security Advisory Council (OSAC). Furthermore, RSOs conduct more than 3,000 investigations overseas each year on behalf of other U.S. law enforcement agencies.

In Eritrea, the Regional Security Office is dedicated to providing a secure living and working environment for all Americans living in Eritrea. The RSO office in Eritrea is comprised of a Regional Security Officer, an office Management Specialist (OMS) and a Foreign Service National Investigator (FSNI). In the addition to the above personnel, the Regional Security Office manages a Local Guard Force (LGF), which provides perimeter protection to the Embassy and residences of Official Americans.