In addition, posting as a diplomat improves the intelligence officer's access to some potential sources; as a diplomat, he would, without raising suspicion, meet with host-government officials in the course of his ordinary business, as well as with other countries' diplomats stationed in the same capital. Indeed, since other countries will also use official cover for their intelligence officers, he will have "innocent" opportunities for meeting them as well.⁵

Also, stationing intelligence agents in an embassy under official cover guarantees that if a national of the host country approaches the embassy with sensitive materials of an offer to provide them, the matter can be handled by an intelligence professional. In this sense, the existence of official cover intelligence officers eases attempts by host-country nationals to make contact with the intelligence service; such positions serve as useful and perhaps necessary "mailboxes," especially in countries that strictly regulate or prohibit their nationals' travel to or communication with the outside world.⁶

Finally, official cover has certain administrative conveniences. The officer can be paid, and other personnel matters can be handled, through regular government channels, and secure communication with the intelligence service's headquarters can be conveniently maintained through the intelligence "station" (the group of intelligence officers under official cover).⁷

At the same time, however, official cover has several drawbacks. Most importantly, because of the relatively small number of officials posted to a given host country, that country's counterintelligence service may be able to determine, fairly precisely, which "diplomats" are intelligence officers and which are not. This may be done by the obvious, if laborious, methods of maintaining surveillance on each official and noting his or her movements and contacts, tapping telephones, bugging apartments, and so forth. The practice of hiring nationals of the host country to work in embassies in various support capacities probably facilitates such surveillance, especially in those countries where it must be assumed that anyone allowed to work in a foreign embassy has agreed to cooperate with the host country's intelligence service.⁸ In addition, simpler and less expensive methods may be able to accomplish the same goal. For example, materials published by a country might be used to trace the careers of its foreign service officers and thus identify patterns that indicate an intelligence connection.

Furthermore, while official cover may provide easy access to some potential sources (primarily other diplomats and officials of host-country national security bureaucracies), it may hinder access to others who might be hesitant to deal with foreign officials, either in general or with those from a particular country. In any case, potential recruits are immediately put on notice that they are dealing with an official of a foreign government, and that may make them more cautious. In addition, if diplomatic relations are broken off, as might happen in case of an intense crisis or war -- when good intelligence may be most necessary -- official-cover officers must leave the country, thereby disrupting the operation of any networks of sources they had established.⁹

The advantages and disadvantages of nonofficial cover are, for the most part, the obverse of the considerations already discussed. on the one hand, since they pose as members of a variety of professions and strata of society, nonofficial-cover officials (NOCs) can have access to a different, and perhaps wider, spectrum of potential sources. Similarly, they can pose as (or, indeed, be) nationals of the country to which they are posted or of some third country. Obscuring the connection with the government for which they work may help them make contact with potential sources and gain access to information. If diplomatic relations are broken off, they may be able to remain and continue to operate. In general, NOCs should also be much harder for the host government to identify.

On the other hand, nonofficial cover suffers from many disadvantages. The expense and administrative difficulty involved in providing nonofficial cover is much greater than in the case of official cover. One method is to persuade a corporation or other private organization to allow an intelligence officer to pose as a member of its staff. Alternatively, the officers may themselves establish businesses or engage in activities that provide plausible explanations for their presence in the target country. The drawback here is that this may not only be expensive but require the intelligence officer to devote a great deal of time to his or her "cover" activity if the cover is to be persuasive, which reduces the time and effort the officer can spend on the primary task of intelligence collection.¹⁰ Communications are likely to be more difficult, since an NOC cannot make regular use of the embassy's communications facilities without raising some of the very suspicions that nonofficial cover is intended to avoid.

One well-known and particularly successful NOC was Richard Sorge, a German citizen and correspondent for a leading German newspaper who spied for Soviet military intelligence in China and Japan from the 1930s until his arrest in the fall of 1941. His close relationship with the staff of the German embassy in Tokyo, including the ambassador, gave him extraordinary access to information about German and Japanese war plans. Shortly before his arrest, Sorge reported to Moscow the critical information that "the Soviet Far East can be considered safe from Japanese attack." According to Sorge's report, Japan had decided not to attack the Soviet Union; instead it would strike south and east in the Pacific against the United States and the British and Dutch colonies in Southeast Asia. Reassured by Sorge's reporting, Stalin felt free to transfer hundreds of thousands of troops from the Far East to Moscow, where they would help stop the German advance in the winter of 1941-42. In retrospect, halting the Wehrmacht outside Moscow was to be a critical turning point in the war.¹¹

Another example of the successful use of nonofficial cover, an example that illustrates the value of being able to disguise one's nationality, is that of Israeli agent Eli Cohen. An Egyptian-born Jew, Cohen emigrated to Israel in 1956 at the age of thirty-two and volunteered his services to Israeli intelligence. He was sent by the Israeli intelligence agency, the Mossad, to Argentina in 1961 to build a cover as an Arab businessman, under the pseudonym Kamal Amin Taabet. After quickly establishing a wide range of contacts in the Syrian expatriate community of Argentina, Cohen moved to Damascus in early 1962. Armed with letters of introduction provided by his new Syrian friends back in Buenos Aires, Cohen was able (with some luck) to establish himself within Syria's ruling circles. In fact, he was so well connected that at one point eh was used as an emissary between a new Ba'athist government and an exiled former president of Syria; at another point, he was thought to be in line for a post in the cabinet of the Syrian government itself. However, after reporting on Syrian political, military, and diplomatic matters for three years, Cohen was caught by Syrian counterintelligence and executed in May 1965.¹²

A particularly ambitious use of nonofficial cover involves officers who enter the host country in the guise of ordinary immigrants. obviously, it is easier to insert such officers into a country that routinely receives a large number of immigrants and is relatively casual about controlling its borders than into one that does not receive immigrants, generally keeps a watch on visitors, and guards its borders carefully.

An interesting example that illustrates how much time and effort the Soviet Union was willing to devote to operations of this type is that of Ludek Zemenek, a Czech national recruited by Soviet intelligence (the Committee of State Security, known as the KGB from its Russian initials).¹³ Given the identity of a Rudolf Herrmann (the real Rudolf Herrmann having been a German who died in the Soviet Union during World War II), he lived in East Germany for about a year. Then, at the end of 1957, he left with an East German wife (also a Soviet intelligence officer) and an infant son for West Germany, where he appeared to be an ordinary East German refugee.¹⁴

After four years in West Germany, Herrmann emigrated to Canada, where he eventually established a small business producing advertising and commercial films. He fulfilled various minor tasks for the KGB, such as filing "personality reports" on politicians and journalists he met through his business, and maintaining communications with a Canadian professor who was a KGB agent. His most important mission, however, was to preserve his cover so that he would be able, in case of a break in diplomatic relations between the USSR and Canada, to take control of the network of Canadian sources form the legal "resident" (chief of the KGB station at the Soviet embassy in Ottawa).

After six years in Canada, Herrmann was instructed to move from Canada to the United States, where he performed similar tasks. When his son Peter was seventeen, Herrmann recruited him to work for the KGB as well. Since Peter had been brought to West Germany as an infant and had been raised from the age of four in Canada and the United States, his background would not give rise to any suspicion; he was to prepare himself for a career in the U.S. government, where he could operate as a long-term Soviet source, or "mole." Presumably, he would have been able to do so had the FBI not confronted father Herrmann several years later and, by threatening to arrest him, his wife and his son, obtained his cooperation.

The mix of official and nonofficial covers a government employs in carrying out its human collection activities will depend on a number of factors. Broadly speaking, the two most important are the type of intelligence being sought and the means available for acquiring it. In the case of the United States and its allies during the Cold war, human collection against the Soviet Union as focused principally on the intentions of the Soviet leadership, the nation's military capabilities, and its intelligence services' efforts against the West. This focus, combined with the close surveillance of all foreigners by Soviet security services, meant that human collection efforts by the United States and other countries came to rely chiefly on intelligence officers operating under official cover.

In contrast, in recent years China has relied heavily on nonofficial cover to carry out its collection program in the United States. Although China's intelligence services do conduct some traditional recruitment and collection using official cover, Chinese humint routinely employs a variety of NOC mechanisms, including front companies, scientific and student exchange programs, and commercial and scientific delegations. Chinese intelligence also uses long-term "sleeper" agents who immigrate from China and establish themselves as residents for an extended period before carrying out intelligence-related activities in the countries to which they have emigrated. This extensive use of nonofficial covers follows form the priority that the Chinese government has given to acquiring advanced American technology and related information, the relatively open nature of U.S. commercial markets, the ease of establishing residence in the United States, and the existence of a substantial American-Chinese ethnic community into which recent immigrants can blend.¹⁵

» Types of Intelligence Sources

Just as we may classify intelligence officers as official cover or NOC, we may make distinctions among types of intelligence sources. One basic distinction is between sources whom the intelligence officer, after preparing the ground, actively recruits into the service of the intelligence agency and walk-ins, who volunteer to assist the intelligence agency of a foreign country, sometimes literally by walking into its embassy.

Recruited sources are generally considered more reliable, since the intelligence officer has had a chance to study their character and motivation before attempting to recruit them.¹⁶ In addition, sources to be recruited will have been chosen on the basis of their access to important information. However, the identification and recruitment of sources is a laborious and time-consuming endeavor, and there is no guarantee that even the most carefully chosen and studied potential source will in fact respond positively to the recruitment attempt, or "pitch."

Walk-ins, on the other hand, are inherently suspect, since there is always the possibility that the supposed volunteer has in fact been dispatched by his own country's intelligence service to pass false or misleading information, inform his country about the opposing service's methods of operation, or entrap one of the opposing service's intelligence officers so as to bring about his or her arrest or expulsion. However, an intelligence service that is too suspicious of walk-ins may miss opportunities to obtain information that it could have easily had. Intelligence lore and history contain stories of walk-ins who were at first ignored or spurned but turned out to b valuable intelligence sources.

A famous case of this sort involved Fritz Kolbe, a German foreign ministry official during World War II. Kolbe's job included sorting through the mass of cable traffic that flowed into Berlin daily from German embassies around the world. The cables regularly touched on sensitive strategic, military, and intelligence subjects as well as diplomatic matters. Having managed to be assigned occasionally as an official courier, Kolbe traveled to Switzerland in August 1943 carrying nearly two hundred documents taken from the files of the foreign ministry in Berlin. He first approached the British embassy in Bern. Wary of "agents provocateurs" or German plants, the British rebuffed Kolbe's approach. He then turned to Allen Dulles, the head of U.S. intelligence operations in Switzerland. Cautious, but less so than their British allies, the Americans worked with Kolbe, who in subsequent trips to Bern provided them with more than 1,500 secret German documents. Kolbe was perhaps the greatest espionage success of the war for the United States.¹⁷

In addition to classifying sources, we can also distinguish among the reasons why they provide information. Sources may be motivated by ideological, ethnic, or religious loyalties that are stronger than their ties to the countries of which they are citizens; they may be disillusioned by the actions of ideologies of their own countries; they may be greedy; they may be somewhat unbalanced people who wish to bring some excitement into their lives; they may desire to avenge what they see as ill treatment by their government; or they may be subject to blackmail. The relative importance of these motives depends on the characteristics of the societies involved and on the tactics of the opposing intelligence services.

For example, the history of Soviet human intelligence collection against the United States and Great Britain since the 1930s shows a substantial shift from ideology toward greed and revenge as reasons Americans and Britons were willing to betray their countries. In the 1930s, the Soviets found that the appeal of communism to many Cambridge University students and instructors, including some from prominent families, made the ideological atmosphere very favorable. Among the students recruited at that time who later became major Soviet agents within the British government were Guy Burgess, Donald Maclean, and Harold ("Kim") Philby.¹⁸

On the other hand, Americans and Britons who were arrested for espionage on behalf of the Soviet Union in the late 1970s and 1980s appear to have been motivated mostly by greed.¹⁹ In another instance, that of Edward Lee Howard, a former CIA officer who gave the Soviets important operational details concerning the agency's activities in Moscow, the motive was revenge against the CIA, for its having fired him.²⁰

In general, the popular imagination probably overestimates the use of sex to gain secrets and the prevalence of blackmail as a reason for espionage, although the potential for blackmail may enable an intelligence officer to keep active a source who had become a spy for some other reason but later on wants to quit. Even so, some cases involving seduction and blackmail of the sort featured in popular spy novels have come to light.

For example, there were the Mata Hari-like exploits of Betty Pack during World War II. Married to a British diplomat, the American-born Pack worked for both British and American intelligence. Her technique consisted largely of having affairs with key foreign government officials. Among her considerable accomplishments, she collected valuable diplomatic information from the Polish foreign ministry before the war, obtained important data on Polish cryptologic efforts to break German codes, completely compromised the internal workings of the French (Vichy) embassy in Washington, and acquired French and Italian naval ciphers.²¹

More typical than seduction, however, is the use of sex to entrap and then blackmail an official who has access to sensitive materials or information. A classic case of this type involved Maurice Dejean, the French ambassador to Moscow in the 1950s and 1960s. Taking note of the married ambassador's roving eye, the KGB assigned a beautiful co-optee (a Soviet citizen pressured to cooperate) to seduce him. Once the affair was well along, the couple was surprised by the "unexpected" return of her "husband." "Outraged," he threatened to make the matter public and take the ambassador to court. Dejean confided in a Russian "friend" -- in reality, the senior KGB officer who had orchestrated the operation from the start; the "friend" offered to help keep the whole matter quiet. The KGB's plan was to use this compromising situation to blackmail Dejean into working for them when he returned to France and, they hoped, was given an even more senior post. However, the Soviets' scheme was spoiled by the defection of a Russian film writer who was privy to the plot.²²

» Problems of Human Intelligence Collection

Many problems encountered in human intelligence collection are inherent in the nature of the enterprise, while others are more specific to the nature of the intelligence target. Of the former, the most critical is ensuring quality control -- being confident that the information sources provide is genuine.

Sources may, for pecuniary motives, either fabricate information or imaginatively repackage and embellish publicly available material to make it appear to have come from highly placed inside sources (creating, to use intelligence jargon, a "paper mill"). The history of intelligence contains occasional examples of clever paper-mill operators who bilked their clients of large sums of money.

Such paper mills flourished in the late 1940s and early 1950s, exploiting the Western intelligence services' difficulty in operating in the communist countries of Eastern Europe. Often they were run by impoverished emigres from those countries, who soon discovered they could make a living by selling "information" they claimed to receive from acquaintances among their former countrymen who had risen to important positions in the new communist governments. Since many of the emigres were well educated and politically sophisticated, they were able to embellish and interpret publicly available information to produce convincing intelligence reports.²³

A more serious quality-control problem arises form the possibility that an agent has been "doubled" -- that he is secretly working for his supposed target and that the information he is providing to his supposed employers is intended to deceive them. Such doubling can occur when an intelligence source is apprehended and chooses to cooperate with his captors to avoid punishment.²⁴ Alternatively, the source could have been a "double agent" (a supposed intelligence source who is really working for the country he appears to be spying on) from the beginning as was noted above in the discussion of walk-ins.

Some of the most interesting and remarkable stories in intelligence history concern the use of double agents. For example, in what was called the "double-cross system," the British succeeded in gaining control of, and running, the entire German human intelligence collection effort in Great Britain during World War II. From almost the beginning of the war, the British controlled all intelligence reports transmitted home by Germany's supposed agents in Britain. Among other achievements, these reports helped deceive the Germans about the location and nature of the D-day landings in Normandy. Even as late as June 9, 1944, three days after D-day, a message from a British-controlled source was instrumental in retaining a German panzer division in the Calais area (to repel the supposedly imminent landing of a "main force" that in fact did not exist), thereby helping the real invasion force in Normandy to secure its foothold.²⁵

Other problems derive from the nature of the target. The more effective and pervasive a target country's internal security apparatus, the more difficulties it poses for human intelligence collection in that country. A government that maintains close control over international travel and communications, as well as over the movements, communications, and economic activity of its people generally, can make it extremely difficult for nonofficial cover, or "illegal," intelligence officers to travel to the country, set up their "cover" activities, and operate without being detected. Official-cover officers can be subjected to intensive surveillance, making it hard for them to meet with citizens of the target country without being observed. The result is what is termed in U.S. intelligence jargon a "hard target" or "denied area," a country in which intelligence activities can in general proceed only under official cover and then only with great difficulty.

Other targets pose particular trouble as well. For example, the collection of intelligence about terrorism is hampered by the relatively small, secretive, and tightly knit nature of most terrorist groups. (Similar considerations apply to human intelligence collection against organized crime.) To the extent that membership in these groups depends on long acquaintanceships, family ties, or previous criminal acts, it becomes very difficult to insert an intelligence source into them (in intelligence jargon, to "penetrate" them). Similarly, the loyalties existing within such a group (to say nothing of the discipline it can impose on its members) make it difficult to persuade an existing member to betray it.

The difficulties do not come to an end even if a source is inserted successfully into a terrorist group. To remain a member in good standing, the source must provide material support for, or participate in, terrorist actions. Yet most intelligence agencies feel obligated to put some limit on actions an officer or source can take to preserve his bona fides. At the same time, using the information provided by the source to warn against or otherwise thwart planned terrorist acts may make it clear to the terrorists that there is an informant in their midst, thus endangering the source's life. Thus, it is often not until a member has been apprehended that an agency gets an opportunity to look into the inner workings of groups of this type.

» Tradecraft

The particular methods an intelligence officer uses to operate and communicate with sources without being detected by the opposing intelligence service are known collectively as "tradecraft." The most serious problem an intelligence officer faces is that the opposing side is likely to keep him under surveillance (that is, watch and follow him) to monitor his activities and identify those with whom he comes in contact. The officer's task, then, is to determine whether he is under surveillance, and if so, to escape that surveillance long enough to contact sources or potential sources without giving away their identities.²⁶

A technique for escaping surveillance that the CIA apparently teaches its officers is illustrated by the ruse employed by Edward Lee Howard, the cashiered CIA officer, to escape FBI surveillance in 1985. Returning home at night in his car, his wife at the wheel, and believing he was being followed by the FBI, Howard had his wife make a sharp turn at a dark intersection; immediately after she turned the corner, he opened the passenger-side door and rolled out. At the same time, Howard's wife pushed up a dummy in his place, making it appear to anyone following from a distance that Howard was still in the car. She then drove home, entered the garage, and pulled down the garage door, leaving the surveillance team unaware that Howard had escaped their surveillance and was now able to move freely, without being followed.²⁷

More typically, an officer may spend several hours traveling by a circuitous route to a meeting, taking several different forms of transportation. If he notices that the man who sits next to him on a westbound subway also happens to be on his eastbound bus, he may reasonably conclude he is being followed. The surveillance team may try to avoid discovery by using a relay system so the same individual is not tailing the officer all the time. The game of surveillance and counter-surveillance can be complicated almost indefinitely.²⁸

Tradecraft also includes techniques for communicating with a source without having to meet with him or her at all. For example, an officer may unobtrusively hand a package or piece of paper to a source as they pass on the street (a "brush pass"). If done correctly, the maneuver may not be observed by the opposing side's surveillance. The officer may place his briefcase on the floor next to his chair as he enjoys a drink in a cafe; the source takes the table next to his and places his own briefcase, identical in appearance to the officer's on the floor next to it. When the source leaves, he takes the officer's briefcase instead of his own. Again, unless the surveillance has carefully watched the putting down and taking up of the briefcase, the switch may not be noticed.

Similarly, an officer may leave a note at an arranged location, such as in a hollow tree in the park; some hours later, the source retrieves it (a "dead drop").²⁹ If the officer places the note without being observed, anyone maintaining surveillance on him to determine his contacts will simply continue following him, not realizing that the meeting has in effect already occurred. Robert P. Hanssen, an FBI counterintelligence specialist recently charged with spying for the Soviet Union and then the Russian Federation for more than fifteen years, communicated almost entirely by means of "dead drops"; evidently, based on his own knowledge of FBI procedures, he considered that the safest method.³⁰

Another precaution is for an intelligence service to avoid, if possible, meeting a source in the country against which he is spying. It is likely to be much safer to meet in a third country, where surveillance may be less vigilant or non-existent. For example, the Soviet Union often preferred to meet particularly important U.S. sources, such as John Walker (who provided the Soviets with vast amounts of classified information relating to naval communications and operations) in Austria, a country that, although a Western-style democracy, was officially neutral in the Cold War.

The Walker case revealed how carefully the Soviets handle an important agent. Most of his meetings with the Soviets were in Vienna, Austria. … During these meetings, Walker and his KGB contact would walk the streets[,] … [never using] a safe house to meet in, as his contact had come directly from Moscow and the Vienna rezidentura (residency, the group of KGB officers working out of a Soviet embassy) was unaware of the operation.³¹

In other cases, intelligence services operating against the United States have preferred to meet sources in Canada or Mexico. These are logical choices, given the ease with which Americans can visit these countries and the large numbers who do so. For example, CIA linguist and analyst Larry Wu-tai Chin, a long-time spy for the People's Republic of China, made frequent trips to Toronto to be debriefed by his handler and to pass undeveloped film to him.³²

Other classic means for intelligence officers and sources to communicate without having to meet in person involve "secret writing" and "microdots." These techniques are useful in cases in which the officer and source have an innocent ostensible reason for communicating with each other but suspect that their letters are likely to be opened and read by the opposing side. To use secret writing, the officer or source would first write an innocuous cover letter. He would then write, typically using a specially treated piece of carbon paper, a secret message on top of the original letter. The message is invisible to the naked eye and becomes legible only when treated by a particular chemical agent known only to the intelligence service for whom the officer and source are working. Microdots are a second means of communicating; in this case, photographs are shrunk to microscopic size and hidden somewhere on the letter, perhaps under the stamp, the flap of the envelope, or on top of punctuation marks in typed letters.

» Defectors

So far, the discussion ahs dealt only with intelligence sources who remain in place -- that is, who report information while retaining the official position that gives them access to it. This is obviously the best situation from the point of view of intelligence collection, since it implies continuing access to information, as well as the potential to "task" the source to obtain specific documents or pieces of information that are particularly necessary or useful. But it requires that the communications between the source and his handler remain hidden, and it exposes the source to the risk of being caught.

In a denied area, these difficulties are magnified. As a result, human intelligence collection against such countries often depends heavily on defectors. From the intelligence point of view, these are sources who do not remain in place but rather flee their countries, typically illegally, and are granted asylum. In the post-World War II period, human intelligence collection by the West against the Soviet Union depended heavily on such individuals. For example, in the early 1950s, Western intelligence services had little success in recruiting Soviet intelligence officers. However, in 1954, in the space of four months, five officers defected to the West. These defections resulted in a wealth of information about Soviet intelligence operations in the decade following World War II. Through the defections, important new intelligence was learned about he KGB's security practices and operational tradecraft, its efforts at breaking the codes of other governments, its penetrations of Western governments, and its involvement in assassinations.³³ Similarly, the defection of Hussein al-Kamal, Iraqi dictator Saddam Hussein's son-in-law, in August 1995 provided valuable information about Iraq's covert weapons program to develop biological weapons that had not been uncovered by the United Nations inspection commission (UNSCOM) during the previous four years.³⁴

Despite their importance, defectors present the same problems as walk-ins. It is difficult to be certain that they are genuine defectors rather than loyal citizens sent out by their government to deceive the opposition. Some skepticism is obviously required in dealing with them, at least initially. The conflicting information provided by several major Soviet defectors to the United States -- in particular, concerning the presence or absence of a highly placed Soviet mole in the American government -- has never been completely sorted out; it bedeviled U.S. intelligence of a quarter of a century.³⁵

2 Unfortunately, the commonly used term "agent" is ambiguous: it usually refers to the source, although sometimes, as in the lexicon of the U.S. Federal Bureau of Investigation (FBI), it refers rather to the intelligence officer.

3 For the sake of simplicity, this discussion is in terms of intelligence officers tasked with spying on countries to which they are posted. This is not necessarily the case; officers may be posted to Freedonia to recruit Ruritanians (such as foreign service, intelligence, or military officers) who are also stationed there. In this case, the officers may be declared (their intelligence connection revealed) to the Freedonian authorities; the purpose of their cover would be to avoid arousing Ruritanian suspicions. Also, intelligence officers may work in their own country to recruit foreign diplomats stationed there.

4 In other intelligence lexicons (such as that of the former Soviet Union), a related distinction between "legal" and "illegal" officers takes the place of the official cover/nonofficial cover (NOC) one. The reference is not to whether the officer's presence in the host country is legal but to his means of communicating with his intelligence headquarters. An illegal officer is one who communicates directly with his intelligence headquarters, without maintaining contact with the "legal" establishments in the host country (the embassy, consulate, trade office, or so forth). In this way, an illegal is similar to an NOC.

5 Paradoxically, in some cases surveillance of foreign embassy personnel and foreigners generally by a country's secret service is so tight that the only safe way to communicate with a source in that country's government is for an intelligence officer working under diplomatic cover to contact him in a relatively "open" manner. For example, in the case of Oleg Penkovsky, a colonel in Soviet military intelligence (GRU) who worked for American and British intelligence in the early 1960s, a key operational question was how to contact him in Moscow, where Soviet counterintelligence surveillance made it extremely risky to attempt to meet or communicate with him clandestinely. One solution was to make use of the fact that Penkovsky met various British and American diplomats in the normal course of his work with science and technology. An intelligence officer could pose as such a diplomat; he would use a predesignated signal (such as wearing a tie clip with red stones) to allow Penkovsky to recognize him. After identifying his contact at some routine diplomatic function, Penkovsky would be told he could

go to the toilet, say, and [the diplomat/intelligence officer] could follow five minutes later and pick up your message. There is no need for personal conversation or anything. [Such meets were] … safe because you know within two or three minutes that the material is in safe hands and the business is completed. There is no need to travel around. … [T]his is the method which gives … the greatest security.

Unfortunately, other less safe method were more frequently used, and it has been suggested that this contributed to Penkovsky's being identified a spy and his eventual arrest and execution. See Jerrold L. Schecter and Peter S. Deriabin, The Spy Who Saved the World (New York: Scriber, 1992), 98, 287-99, 314-15, 409-11.

6 For this "mailbox" function to work, it must be generally understood, even if not officially acknowledged, that an embassy or diplomatic establishment has on its staff officials capable of handling sensitive or secret information from unsolicited sources. An example of the quasi-public character of this kind of intelligence work is provided by Allen Dulles, the former director of central intelligence. According to Dulles, soon after he was sent as an intelligence officer to Switzerland during World War II, a leading Swiss journal published a story describing him as President Roosevelt's secret and special envoy. "Offhand," Dulles noted, "one might have thought this unsought advertisement would have hampered my work. Quite the contrary was the case. … As a result [of the story], to my network flocked a host of informants, some cranks, it is true, but also some exceedingly valuable individuals." Allen Dulles, The Craft of Intelligence (New York: Harper and Row, 1963), 7.

7 The intelligence operation is designated by various terms, for instance, "station" (in U.S. parlance) and "residency" (rezidentura, in Soviet and Russian parlance.)

8 The problems arising from allowing host-country nationals to work in an embassy are long-standing ones. Writing about his tenure as the U.S. minister to St. Petersburg, Russia, in the early 1830s, James Buchanan remarked, "We are continually surrounded by spies both of high and low degree. You can scarcely hire a servant who is not a secret agent of the police." Mission to Russia (New York: Arno, 1970), 339.

For a more recent, journalistic account of the security problems posed by the extensive use of host-country nationals in an embassy, see Ronald Kessler, Moscow Station: How the KGB Penetrated the American Embassy (New York: Scribner, 1989).

9 For example, the occupation of the U.S. embassy in Teheran in November 1979 (and the taking hostage of its personnel) apparently shut down U.S. human intelligence collection in Iran completely. When planning began for the military operation to rescue the hostages, there were "no American agents on the ground," and the CIA was apparently forced to slip an agent back into Iran to help gather information required for planning the rescue attempt. Charlie A. Beckwith and Donald Knox, Delta Force: The U.S. Counterterrorist Unit and the Iran Hostage Rescue Mission (New York: Harcourt Brace Jovanovich, 1983), 196-97, 220-21.

10 Cover may be provided by a business established, owned, and run by the intelligence service itself; such an organization is known as a proprietary. A proprietary may be useful for covert action purposes as well as for providing cover for intelligence officers. For example, a shipping business could facilitate the clandestine transporting of arms and supplies to insurgents.

11 Earlier in 1941, Sorge had reported that Germany intended to break its nonaggression pact with the Soviet Union and attack it in June. His reports on Hitler's intent to break the accord and the specific date for the start of the German offensive were ignored by Stalin. The Soviet dictator was apparently convinced that this and similar intelligence about German perfidy had been fabricated by the British to provoke a rift between Germany and the Soviet Union and push Moscow into an alliance with London. It appears that Stalin gave Sorge's reports on Japanese intentions greater credence in part because they were corroborated by Soviet intercepts of Japanese diplomatic messages. For an account of Sorge's life and activities as a Soviet intelligence officer, see Gordon W. Prange, with Donald Goldstein and Katherine V. Dillon, Target Tokyo: The Story of the Sorge Spy Ring (New York: McGraw-Hill, 1984).

12 For an account of Cohen's life as an Israeli agent, see Stanley A. Blumberg and Gwinn Owens, The Survival Factor: Israeli Intelligence from World War I to the Present (New York: Putnam, 1981), 208-24.

13 This account is based on John Barron, KGB Today: The Hidden Hand (New York: Reader's Digest, 1983; New York: Berkley, 1985), 247-314.

14 Of the members of the Soviet bloc, East Germany was particularly adept at placing NOCs (or, to use the Soviet term, "illegals") in the West, especially in West Germany, its principal target. In part, the use of illegals was forced on East Germany, since its failure during the first half of the Cold war to achieve wide diplomatic recognition meant that it lacked embassies and consulates in many noncommunist countries. It was also facilitated by the fact that West Germany actively encouraged immigration from the East. According to a former East German intelligence officer, there were two to three thousand agents in place by the late 1950s. The most famous was Guenther Guillaume, who was so successful in penetrating the West German political elite that he became personal secretary to Chancellor Willy Brandt. He served in this position from 1969 until his arrest in 1974. Christopher Andrew and Oleg Gordievsky, KGB: The Inside Story (New York: HarperCollins, 1990; HarperPerennial edition, 1991), 448-50. For an account of East Germany's use of illegals form the operational perspective of a former East German intelligence officer, see Werner Stiller, with Jefferson Adams, Beyond the Wall: Memoirs of an East and West German Spy (Washington, D.C.: Brassey's [U.S.], 1992), 41-118, passim.

15 For an overview of Chinese humint activities, see Nicholas Eftimiades, Chinese Intelligence Operations (Arlington, Va.: Newcomb, 1998), chap. 5, 28-44. On China's program to acquire U.S. high technology, see the "Cox Committee Report": Report of the Select Committee on U.S. National Security and Military/Commercial Concerns With the People's Republic of China (Washington, D.C.: Government Printing Office, 1999), chap. 1, available at www.house.gov/coxreport. See also "China's High-Tech Espionage," a two-part review of Sources and Techniques of Obtaining National Defense Science and Technology Intelligence, a Chinese "handbook" on spying in the West in National Counterintelligence Center [hereafter NACIC], Counterintelligence News and Developments (June and September 2000), vols. 2 and 3. The reviews can be found at www.nacic.gov, the NACIC Website.

16 Nevertheless, the possibility cannot be ruled out that the source, after being approached by a foreign intelligence officer, may report the recruitment attempt to his own government and be instructed to "play along."

17 See Joseph E. Persico, Piercing the Reich: The Penetration of Nazi Germany by American Secret Agents during World War II (New York: Viking, 1979), 62-72, 328.

18 Burgess and Maclean both served at the Foreign Office, while Philby joined the British foreign intelligence service (MI6) and rose to be head of its counterintelligence section and its Washington-based liason officer with the CIA and FBI. See Andrew Boyle, The Fourth Man (New York: Dial, 1979), for an account of the Soviet spy ring that had its roots in Cambridge University in the 1930s. See also Robert Cecil, "The Cambridge Comintern," in The Missing Dimension: Governments and Intelligence Communities in the Twentieth Century, ed. Christopher Andrew and David Dilks (Urbana: University of Illinois Press, 1984).

19 Defense Security Service, Security research Center, Recent Espionage Cases, 1975-1999 (September 1999), available at www.dss.mil/training/pub.htm, contains an overview and summaries of recent cases. Various motives for engaging in espionage are analyzed in Theodore R. Sarbin, Ralph M. Carney, and Carson Eoyang, eds., Citizen Espionage; Studies in Trust and Betrayal (Westport, Conn.: Praeger, 1994).

20 David Wise, The Spy Who Got Away: The Inside Story of Edward Lee Howard (New York: Random House, 1988).

21 See Mary S. Lowell, Cast No Shadow: The Life of the American Spy Who Changed the Course of World War II (New York: Pantheon, 1992).

22 For an account of the Dejean affair, see John Barron, KGB: The Secret Work of Soviet Secret Agents (New York: Reader's Digest, 1974), 114-40.

23 Allen Dulles, The Craft of Intelligence (Boulder, Colo.: Westview, 1985), 216.

24 If the captured spy refuses to cooperate, it may be possible for the intelligence service that captured him to impersonate him by sending messages in his name. This could work in situations, such as wartime espionage on enemy territory, where the source would not be expected to have face-to-face meetings with his employers.

25 Christopher Andrew, Her Majesty's Secret Service: The Making of the British Intelligence Community (New York: Viking, 1986), 488. For a report on the "Double-Cross System" by the man who managed it, see J.C. Masterman, The Double-Cross System in the War of 1939 to 1945 (New Haven, Conn.: Yale University Press, 1972).

26 A dated, but still interesting, training manual prepared by Soviet military intelligence provided lessons on how to communicate with and control intelligence sources in the United States. It was among the materials provided by Oleg Penkovsky, a Soviet military officer who spied for the United States and Britain in the late 1950s and early 1960s. "The Prikhodko Lecture" in The Penkovsky Papers, ed. Frank Gibney (New York: Doubleday, 1965), 102-62.

27 Wise, The Spy Who Got Away, 198-205. To complete the ruse, on her return home Howard's wife called Howard's doctor's office. At that hour, the doctor was predictably not in his office, and his answering machine came on; Howard's wife, assuming the phone was tapped, played into the phone a taped message for his doctor that Howard had recorded earlier. This would help the FBI confirm that Howard had returned home with his wife. As it turned out, the Howards' efforts were unnecessary; inexplicably, the FBI agent responsible for watching the house had missed the Howards' departure in the first place, and the Howards' car was in fact not being followed at all.

28 An example of this interaction between surveillance and countersurveillance is described by Peter Wright, an ex-MI5 (British counterintelligence) official, in his book Spycatcher. According to Wright, Soviet technicians operating in their London embassy were able to monitor the communications of the mobile surveillance teams (the "Watchers") used by MI5. By analyzing those communications and correlating them with their own operations, the Soviets could deduce whether a particular meeting between a Soviet intelligence officer and his source was likely to be surveilled. If it was, the officer would be alerted to scrub the meeting. British counterintelligence, according to Wright, was able to identify this weakness in its surveillance system when it detected from within the Russian embassy electronic emissions that were uniquely associated with the Soviets' radio intercept operations of the Watcher communications. In brief, as Wright tells it, MI5 was watching the Soviets watch the Watchers, who, in turn, were busy watching the Soviets. Wright, Spycatcher: The Candid Autobiography of a Senior Intelligence Officer (New York: Viking, 1987), 52-57, 91-93.

29 For an illustration of the particular tradecraft involved in making a "dead drop," see John Barron's account of the Soviet spy ring headed by John Walker, Breaking the Ring (Boston: Houghton Mifflin, 1987), 80-96.

30 The FBI's affidavit in support of the arrest and search warrants in the Hanssen case contains lengthy quotes from the messages passed between Hanssen and the KGB and later its Russian successor agency, the Sluzhba Vneshney Razvedki (Foreign Intelligence Service or SVR). In these messages Hanssen ruled out face-to-face meetings (even in foreign countries) on security grounds and insisted that dead drops be used almost exclusively. (The initial contact was made by mail to the residence of a Soviet intelligence officer; on a few occasions, there was some communication by telephone.) The affidavit is available at www.fas.org/irp/ops/ci/hanssen_affadavit.html; it is a veritable manual of tradecraft on dead drops.

31 Herbert Rommerstein and Stanislav Levchenko, The KGB against the "Main Enemy": How the Soviet Intelligence Service Operates against the United States (Lexington, Mass.: Lexington, 1989), 293. By keeping in the dark the Soviet intelligence officers stationed in Vienna, the KGB also reduced the risk that U.S. surveillance of Soviet intelligence officers there would compromise the Walker operation.

32 Nicholas Eftimiades, Chinese Intelligence Operations (Arlington, Va.: Newcomb, 1998), 33, 36-37.

33 In late 1953, the Soviet intelligence service, then called the MGB (Ministry of State Security), was part of the Ministry of the Interior (MVD); the consolidation of these two important bureaucracies was the result of a power play by former intelligence chief and key Kremlin intriguer Lavrenti Beria in the wake of Stalin's death in March 1953. After Beria's arrest and execution in December 1953, the Soviet intelligence service was again separated form the interior ministry and designated as the KGB (Committee of State Security). It was at the time of this unrest within the intelligence service that these defections took place. The five defectors (and the countries in which they defected) were: Yuri Rastvorov (Japan); Pyotr Deryabin (Austria); Vladimir and Evdokia Petrova (Australia); and Nikolai Khokhlov (West Germany). See Gordon Brook-Shepherd, The Storm Birds: Soviet Post-War Defectors (London: Weidenfeld and Nicholson, 1988), 57-131.

34 According to Stockholm International Peace Research Institute, "Fact Sheet: Iraq: The UNSCOM Experience" (October 1998), 3 available at editors/sipri.se/pubs/Factsheet/UNSCOM.pdf, the significance of Iraq's largest research-and-development and production site for biological weapons, al-Hakam, was unrecognized until Hussein al-Kamal's defection, although UNSCOM inspectors had already visited it. Similarly, the 1994 defection of a leading scientist involved in the Iraqi nuclear weapons program provided the first detailed information about its history and inner workings. Judith Miller and James Risen, "Defector Describes Iraq's Atom Bomb Push," New York Times, August 15, 1998, A1.

35 The story is told in David C. Martin's Wilderness of Mirrors (New York: Harper and Row, 1980). More recent accounts of this debate within the American intelligence community include Tom Mangold, Cold Warrior: James Jesus Angleton and the CIA's Master Spy Hunter (New York: Simon and Schuster, 1991), and Edward J. Epstein, Deception: The Invisible War between the KGB and the CIA (New York: Simon and Schuster, 1989). The Mangold and Epstein books have decided but opposing points of view, reflecting the difficulty of reaching a definitive judgment about the bona fides of some defectors.