The British-American Tobacco Document Collection
Archive maintained by UCSF provides search and browse access to over 6000 BAT documents from the 1950's to the 1990's. Documents cover BAT's marketing, research and development, cigarette analysis and design, and business in developing countries. BAT's efforts toward developing new, "safer" cigarettes gradually change into efforts to make consumers believe that certain cigarettes (low-tar, and the like) are safer.
http://www.library.ucsf.edu/tobacco/batco/.