The current techniques used in forensic geochemical hydrocarbon fingerprinting have their genesis along with the evolution of gas chromatography as it applies to hydrocarbon research. In the United States, a small group of government and academic chemists and marine scientists pioneered the use of gas chromatography in the identification of both natural and petroleum-derived hydrocarbons. Natural products were a primary focus until the research direction was altered somewhat by marine oil spills, accidents releasing crude oil and refined petroleum products to the world’s coastal marine environment, giving rise to concerns regarding biogeochemical impacts. Application of oil spill research continued from that point so that the geochemical research begun in the late 1960s and early 1970s now forms a major component of investigations of petroleum releases both in the aquatic and terrestrial environments. As the capabilities for the identification of individual hydrocarbons in a variety of petroleum products improved with basic advances in chromatographic technology, new applied sciences in forensic geochemical hydrocarbon fingerprinting have emerged. While in the beginning the identification of bulk petroleum products received primary emphasis, current techniques are now capable of distinguishing among a variety of potential sources including those derived from natural processes, undetected individual releases, chronic releases and obvious catastrophic releases. However, a review of the techniques employed in the late 1960s and early 1970s will show that the basic approaches pioneered at that time are still in use today, albeit with a higher level, with concomitant advances in chromatographic technology as the questions grow in complexity.