Clandestine HUMINT (HUMan INTelligence) includes a wide range of espionage sources. This includes the classic spy (called, by professionals, asset or agent) who collects intelligence, but also couriers and other personnel, who handle their secure communications. Other support personnel include access agents who may arrange the contact between the potential spy, and the case officer who recruits them. In some cases, the recruiter and the continuing supervision of the agent may be different people. Large espionage networks may be composed of multiple levels of spies, support personnel, and supervisors. Espionage networks are usually organized on a cell system, where each clandestine operator knows the people in his own cell, perhaps the external case officer, and an emergency method, not necessarily a person, to contact higher levels if the case officer or cell leader is captured, but has no knowledge of people in other cells.

Espionage involves a human being obtaining (i.e., using human intelligence (HUMINT) methods) information that is considered secret or confidential without the permission of the holder of the information. Espionage is inherently clandestine, and the legitimate holder of the information may change plans or take other countermeasures once it is known that the information is in unauthorized hands. See the articles such Clandestine HUMINT operational techniques and Clandestine HUMINT asset recruiting for discussions of the "tradecraft" used to collect this information.

James George Janos (born July 15, 1951), better known as Jesse Ventura, is an American statesman, actor, author, and former professional wrestler who served as the 38th Governor of Minnesota from 1999 to 2003.

Ventura served as a Navy UDT during the Vietnam War. He later embarked on an 11-year professional wrestling career from 1975 to 1986, taking up the stage name Jesse "The Body" Ventura. He had a long tenure in the World Wrestling Federation as a performer and color commentator, and was inducted into the company's Hall of Fame in 2004. After leaving wrestling, Ventura began a successful film career, appearing in films such as 1987's Predator.

Ventura first entered politics as Mayor of Brooklyn Park, Minnesota from 1991 to 1995. He ran as the Reform Party candidate in the Minnesota gubernatorial election of 1998, running a campaign centered on grassroots events and unusual ads that implored citizens not to "vote for politics as usual". The campaign was successful, and Ventura served from January 4, 1999, to January 6, 2003, without running for a second term.

Robert "Bob" Booker Baer (born July 1, 1952) is an American author and a former CIA case officer who was primarily assigned to the Middle East. He is currently TIME.com's intelligence columnist and has contributed to Vanity Fair, The Wall Street Journal, and The Washington Post. Baer is a frequent commentator and author about issues related to international relations, espionage and U.S. foreign policy.

Baer was born in Los Angeles, raised in Aspen, Colorado, and aspired to become a professional skier. He spent many years of his childhood with his mother in Europe before returning to the US. After a fairly poor academic performance during his freshman year at high school, his mother sent him to Indiana's Culver Military Academy. In 1976, after graduating from the Georgetown University School of Foreign Service and entering the University of California, Berkeley, Baer decided to join the CIA's Directorate of Operations (now the National Clandestine Service) as a case officer. Upon admittance to the CIA, Baer engaged in a year's training, which included a four-month paramilitary course and foreign language courses.