Thomson-CSF was a French company that specialized in the development and manufacture of electronics with a heavy focus upon the aerospace and defence sectors of the market.

It operated as an electronics specialist on products such as broadcasting equipment, electroacoustics, shortwave radio sets, radar systems and television.

Thomson-CSF traces its origins to the formation of the American business Thomson-Houston Electric Company by Elihu Thomson and Edwin Houston in 1879.

Two years later, the electronics business of Thomson-Brandt merged with Compagnie Générale de Télégraphie Sans Fil (General Wireless Telegraphy Company, commonly abbreviated as CSF) to form Thomson-CSF.

[2] Prior to the merger, CSF had operated as a pioneer in the fields of broadcasting, electroacoustics, shortwave radio, radar systems and television.

In this period the company diversified into several new sectors, leading to it manufacturing backend telephony equipment, semiconductors and medical imaging apparatus.

Throughout the 1980s, the company's financial position improved dramatically as undertook a major reorganisation, focusing its efforts on the production of electronics for professional and defence customers.

[2] During the late 1980s, Thomson-CSF, anticipating future defence spending cutbacks and a downturn in its lucrative export contracts, initiated a restructuring of its businesses with the aim of maintaining its margins.

[2] During the late 1990s, French Prime Minister Lionel Jospin's Plural Left government initiated a policy of privatisation of several state-owned companies, including Thomson-CSF.

[3][4] During April 1998, several of the affected companies, including Aérospatiale, Alcatel, Dassault Industries, Thomson-CSF and Thomson SA reached a cooperation agreement endorsed by the French government.

[2] The division of the company's consumer electronics and defence businesses prior to privatisation brought about the creation of Thomson Multimedia, which was a distinct entity from Thomson-CSF.

[2] Shortly after its privatisation, the company began exploring the possibility of merging with British defence specialist Marconi Electronic Systems.