 A third audience consists of journalists, government officials, and key businesspersons, who exert a disproportionate influence on a state's foreign or economic policy.A fourth, but less publicized audience, consists of intelligence officers and agents who monitor broadcasts for both open-source intelligence clues to the broadcasting state's policies and for hidden messages to foreign agents operating in the receiving country.The BBC started its monitoring service in Caversham, Reading in 1936 (now BBC Monitoring).