David Nelson Farr (born 1955) is an American business executive. He is the chairman and CEO of Emerson Electric Company, a Fortune 500 company. Farr has worked at the company since 1981. He is married with two children and is a resident of Ladue, Missouri.On October 25, 2011, IBM announced Farr was elected to its board of directors, and he joined the board on January 1, 2012.