Polycyclic aromatic hydrocarbons (PAHs) are the first type of chemicals that were ever discovered to cause cancer in humans. They are found in cigarette smoke, in barbecued and smoked foods, in automobile and Diesel engine exhaust, fireplace smoke, and many other common things that people are exposed to. Analyzing for PAHs in the environment is important in identifying potential sources of cancer exposure and eliminating these as risks. The smaller PAHs, those of lower than 300 molecular weight, have been the most studied and have also been covered in several books. No books have dealt with the analysis of the larger PAHs. These compounds are not only important for the health concerns, but they are also of current technological and scientific interest.