As his interest in symbol application grew, Dreyfuss, his wife Doris and designer Paul Clifton assembled, collated and standardized a data base of 20,000 symbols from throughout the world. By 1972 Dreyfuss and his staff codified and published those symbols in an attempt to create the first unified symbol reference.
Their published work, A Symbol Sourcebook, was essentially a dictionary with symbols organized into categories including basic symbols, disciplines, color, and graphic form. To make the sourcebook truly universal, the table of contents was in written in 17 languages in addition to English.
Dreyfuss was elected as the first president of the Industrial Design Society of America, IDSA. When he learned that a national transportation signage system was being planned, he combined the clout of the IDSA and AIGA to convince the Department of Transportation to oversee the design process.