Sperry-Sun Drilling Services, Inc. provided drilling services and equipment to the petroleum industry, first in Texas and the Gulf Coast and then world wide.

In the late 1920s, J. N. Pew, Jr. (1886-1963) of the Sun Oil Company began planning to develop better well-drilling techiques in the Texas oil fields. Among the principal problems he confronted was a means of measuring and regulating the inclination of the drilling rig, as the drill bit would tend to drift and change direction as it encountered strata of differing hardness and density.

Pew negotiated with gyroscope inventor Elmer Sperry (1860-1930) for special gyroscopes that could be lowered down drill holes with the drilling rig. the Sperry-Sun Well Drilling Company was incorporated on October 9, 1929, as a joint venture of Pew's Sun Oil Company and the Sperry-Gyroscope Company. Sperry-Sun continued to make numerous innovations in well drilling. In 1932, Robert S. Hyer (1892-1951) developed the magnetic method of operation, which enabled the operator to accurately direct the drill bit, a technique that increased in importance with the growth of offshore drilling.

The Sun Oil Company bought out Sperry's interest in 1947. In January 1974, Sperry-Sun absorbed Reamco, Inc., another well drilling service, and was renamed Sperry-Sun, Inc. During a downturn in which Sun underwent considerable restructuring, it sold the Sperry-Sun operation to NL Industries, Inc. for $252 million on April 22, 1981.

NL Industries, the former National Lead Company, was alreaady deeply involved in oil well drilling through its Baroid Division, which made drilling fluids and performed logging services. NL Industries formed a new subsidiary, NL Sperry-Sun, Inc. to continue the business. However, a severe downturn in the oil industry that began in the early 1980s led to many years of poor performance for the parent company. NL Industries, Inc. spun off all its petroleum and chemical services businesses, including Sperry-Sun to a new entity, the Baroid Corporation, in 1988.

Baroid Corporation merged into Dresser Industries, Inc. in 1994. On November 1, 1997, Sperry-Sun Drilling Services, Inc. was merged into Dresser Industries, Inc. as a division called "Sperry-Sun."