American Chemical Society
"The American Chemical Society (ACS) is a self-governed individual membership organization that consists of more than 159,000 members at all degree levels and in all fields of chemistry. The organization provides a broad range of opportunities for peer interaction and career development, regardless of professional or scientific interests. The programs and activities conducted by ACS today are the products of a tradition of excellence in meeting member needs that dates from the Society's founding in 1876."
Source: ACS website