Although the chemical industry can trace its roots into antiquity, it was during the industrial revolution that it started to become an actual industry and began to use the increased knowledge of chemistry as a science and technology to produce products that were needed by companion industries and consumers. These commercial efforts resulted in the synthesis of many new chemicals. Quite quickly, in these early days, previously unknown materials or materials that had been present only in low concentrations, were now in contact with people in highly concentrated forms and in large quantities. The people had little or no knowledge of the effects of these materials on their bodies and the natural biological and physical processes in the rivers and oceans, the atmosphere, and in the ground. Until the end of the nineteenth century these problems were not addressed by the chemical industry and it is only recently that the industry began to respond to public criticism and political efforts. Legal restrictions aimed at preserving the quality of life have been directed at health, safety and longevity issues and the environment. Solvents have always been mainstays of the chemical industry and because of their widespread use and their high volume of production they have been specifically targeted by legislators throughout the world. The restrictions range from total prohibition of production and use, to limits placed on vapor concentrations in the air. As with any arbitrary measures some solvents have been damned unfairly. However, there is no question that it is best to err on the side of safety if the risks are not fully understood. It is also true that solvents should be differentiated based on their individual properties.