THE HISTORY OF INDUSTRIAL analyses of aromatic hydrocarbons began in the 1920s when the production of benzene from coke by-products became commercially viable. By the 1930s, the rapid growth in demand for benzene as well as the commercial production of heavier aromatics led to the formulation of a considerable number of empirical analytical procedures. At this time, ASTM Committee D16 on Aromatic Hydrocarbons was formed. In the more than 50 years that this group has been active, the changes in analytical techniques have progressed hand-in-hand with the advancements in process technology and the expansion in the demand for high-purity aromatic products.