The American Chemical Society is a US-based, "congressionally chartered independent membership organization that represents professionals at all degree levels and in all fields of chemistry and sciences that involve chemistry." Members are in academia, government and industry, and from medicine, engineering, agriculture, and related chemical and pharamaceutical businesses and industries.
The Chemical Abstracts Service (CAS) is a division of the American Chemical Society that indexes and abstracts a large portion of the world’s chemical information and literature. CAS has created and maintains key collections, databases and indexes; produces and distributes tools and interfaces for managing and analyzing chemical related information; and provides an array of services to those in the field of chemistry.
CAS database products serve a variety of scientific disciplines, including biomedical, chemical, materials, and agricultural sciences and engineering. Most users of those products are in academia, the chemical industries and government agencies.