Resident spy In espionage , a resident spy is an agent operating within a foreign country for extended periods of time . A base of operations within a foreign country which a resident spy may liaise with is known as a station in United States parlance and a rezidentura ( residency ) in Russia n parlance ; accordingly , what the U . S . would call a station chief , the head spy , is known as a rezident in Russian . Types of resident spies . In the former U . S . S . R . and Russian nomenclature , there are two types of resident spies : " legal ' nye rezidenty " ( legal resident spy ) and " nelegal ' nye rezidenty " ( illegal resident spy ) . In U . S . parlance the same distinction is between " official cover " and " non - official cover " . A legal resident spy operates in a foreign country under official cover ( e . g . from his country ' s embassy ) . He is an official member of the consular staff , such as a commercial , cultural or military attaché . Thus he has diplomatic immunity from prosecution and cannot be arrested by the host country if suspected of espionage . The most the host country can do is send him back to his home country as persona non grata . An illegal resident spy operates under a non - official cover ; thus , he cannot claim immunity from prosecution when arrested . He may operate under a false name and has documents making him out to be an actual national or from a different country to that which he is spying for . Examples of such illegals include Rudolf Abel who operated in the United States ; and Gordon Lonsdale who was born in Russia , claimed to be Canadian and operated in Britain . Famous Soviet " illegals " include Richard Sorge , Walter Krivitsky , Alexander Ulanovsky , and Anna Chapman , who is also known as a sleeper agent . Comparison of illegal and legal resident spies . The advantages and disadvantages of legal resident spies mostly mirror the disadvantages and advantages of illegal resident spies . A legal resident spy has the advantage of diplomatic status , but the disadvantage of being a known foreigner to the host country and one of just a few official diplomatic staff , whose intelligence status is thus easy for counterintelligence agencies to discern ; whereas an illegal resident spy has the advantage of being unknown as a foreigner to the host country and one amongst millions of the country ' s ordinary citizens , but the disadvantage of not having diplomatic immunity to fall back upon . A legal resident spy has opportunities to meet high - level personnel of the host country as part of his / her " official " business , whereas an illegal resident spy does not . But , conversely , illegal resident spies have easier access to a wide range of potential sources who would be put off by having to approach and deal with an openly foreign official , and indeed need not even reveal to those people what country he / she actually works for . Furthermore : An illegal resident spy can stay in the host country when diplomatic relations break down , whereas legal resident spies are forced to leave with the diplomatic mission . But a legal resident spy is easier to pay , since his / her salary can be openly incorporated into the diplomatic payroll , whereas making arrangements to pay illegal resident spies can be difficult , sometimes involving ruses , more expensive and complex to administer than paying a diplomatic official would be , such as paying a host country organization or corporation to allow the illegal resident spy to pose as a member of its staff and be nominally paid by that organization / corporation . A legal resident spy has full and aboveboard access to embassy facilities , for secure communications , meetings , and other services ; whereas an illegal resident spy has little to no access to such facilities , and communications arrangements are thus more difficult and time consuming . An illegal resident spy will usually have a falsified biography ; whereas a legal resident spy may suffer from having an official biography , documenting his / her diplomatic career and providing useful clues to counterintelligence services about his / her intelligence activities and connections . Further reading . FURTHER reading : Clancy , Tom . Threat Vector .