In addition they may produce HUMINT from overt sources, such as voluntary interviews with travelers, businesspeople, etc. Some of the latter may be considered open source intelligence OSINT and be performed by other agencies, just as reports from diplomats are another form of HUMINT that flows into the State Department.
At times, this function may be assigned to the CIA, because its counter-intelligence staff has biographical indexes that let them check the background of foreign citizens offering information. For example, there may be a name check on a business or scientific contact who meets either with CIA representatives or staff of the National Open Source Enterprise
Read more about this topic: National Clandestine Service