The importance of scientific analysis in criminal matters was identified in the 1920s by the newly appointed Federal Bureau of Investigation (FBI) Director J. Edgar Hoover. In 1932, a proposal was received by Hoover from Special Agent Charles Appel for the development of a separate division within the FBI to handle “crime prevention work” and to oversee a “criminological research laboratory.” In 1932, this proposal became a reality with the establishment of the Criminology Laboratory. In its first year of operation, the Laboratory performed 963 examinations. The Laboratory became an official FBI division in 1942 and was renamed the FBI Laboratory in 1943. Over the last seven decades, the FBI Laboratory has met the needs of the FBI as well as law enforcement agencies worldwide in solving crimes, bringing criminals to justice, and protecting the public. Cases and facts highlighted in this paper provide only a glimpse into the Laboratory’s 75 years of forensic science service, such as the Lindbergh kidnapping, the Lisk-Silva murders, and counterintelligence cases, such as atomic bomb secrets, identification of soviet spies, and ferreting out moles within various government agencies.