Problems with the use of criminal informants have included the FBI's use of undercover agents to infiltrate civil rights groups under J. Edgar Hoover and the FBI's intervention in local prosecutions in Arizona. In 1976, FBI Attorney General Edward Levi established a written set of guidelines that focused on the control of criminal activity by informants. However, both the FBI and Drug Enforcement Administration (DEA) have had problems keeping the names of informants a secret. The New York City Police Department has also attempted to exert administrative control over its informant system, following investigations that revealed pervasive corruption in the department. Arguments for the traditional system of 'working' informants are cited in the article as well as arguments advocating informant control. Problems of pacts made by law enforcement agents with possible career criminals are detailed. Solutions include ensuring that an officer's supervisors know about his relationship with informants, documenting that relationship, or subjecting traditional informant relationships to administrative review. Specific procedures such as the tape recording of an arrestee's account of the assistance he would be willing to provide, as is done by the San Jose Police Department (California), are also given. Photographs are provided.