Who's Who in the CIA was a book written by the East German journalist Julius Mader and published in East Berlin

East Berlin

East Berlin was the name given to the eastern part of Berlin between 1949 and 1990. It consisted of the Soviet sector of Berlin that was established in 1945. The American, British and French sectors became West Berlin, a part strongly associated with West Germany but a free city...

 in 1968 purporting to identify about 3,000 active agents of the U.S. Central Intelligence Agency

Central Intelligence Agency

The Central Intelligence Agency is a civilian intelligence agency of the United States government. It is an executive agency and reports directly to the Director of National Intelligence, responsible for providing national security intelligence assessment to senior United States policymakers...

. It was modelled after other Who's Who

Who's Who

Who's Who is the title of a number of reference publications, generally containing concise biographical information on a particular group of people...

 guides.

According to Ladislav Bittman of the Czechoslovakia

Czechoslovakia

Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...

n StB

STB

STB is an acronym that can mean:* Sacrae Theologiae Baccalaureus – Bachelor of Sacred Theology* Set-top box – a television device that converts signals to viewable images* Simpson Thacher & Bartlett LLP -- a law firm...

, Who's Who was only partly reliable, and was intended as disinformation

Disinformation

Disinformation is intentionally false or inaccurate information that is spread deliberately. For this reason, it is synonymous with and sometimes called black propaganda. It is an act of deception and false statements to convince someone of untruth...

:

About half of the names listed in that book are real CIA operatives. The other half are people who were just American diplomats or various officials; and it was prepared with the expectation that naturally many, many Americans operating abroad, diplomats and so on, would be hurt because their names were exposed as CIA officials.

In response, the CIA assisted journalist John Barron

John Barron (journalist)

John Daniel Barron was a conservative American journalist and investigative writer. He is best remembered as the author of several books dealing with specifics of Soviet espionage.-Early years:...

 in writing his book KGB: The Secret Work of Secret Agents, the appendix of which named 1,600 alleged KGB

KGB

The KGB was the commonly used acronym for the . It was the national security agency of the Soviet Union from 1954 until 1991, and was the premier internal security, intelligence, and secret police organization during that time.The State Security Agency of the Republic of Belarus currently uses the...

 and GRU

GRU

GRU or Glavnoye Razvedyvatel'noye Upravleniye is the foreign military intelligence directorate of the General Staff of the Armed Forces of the Russian Federation...

 officers posted abroad under diplomatic cover. Barron admitted to the New York Times, that he received help from the CIA in writing the appendix.

Who's Who in the CIA was publicized through the early 1990s in the publications Top Secret and Geheim.