According to George E. Davis, the ideal chemical engineer could move from industry to industry, mixing and matching the various operations that the American Arthur D. Little (1863–1935) was later to call "unit operations." Little was among the leaders who defined chemical engineering as a separate profession with a distinct approach and training method.
Little majored in chemistry at MIT before the advent of chemical engineering and was the editor of the college newspaper, The Tech—an experience that prepared him for his role as a spokesperson for chemical engineering education, industrial research, and the American chemical industry. His first jobs made him an expert in the new sulfite process for making paper, and in 1886 he set up a consulting company whose successor, Arthur D. Little, Inc., prospers to this day. From an early date Little also preached against heedless industrial practices, referring ominously to "the handwriting on the wall" for a society that would destroy its own environment.
In 1900 Little formed a new partnership with William H. Walker, a young MIT chemistry instructor, and began aiding him in his charge to revamp MIT's chemical engineering curriculum.