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The Toyota International Series was a professional women's tennis circuit founded in 1977 as the Colgate International Series it consisted of tournaments absorbed from the ILTF Women's International Grand Prix and included all those world wide events that were not part of the Virginia Slims Circuit who's tournaments were mainly in the United States. In 1979 it was renamed as the Colgate Series. In 1981 the Toyota Motor Corporation took over sponsorship of the circuit from the Colgate-Palmolive Company where it resumed under it's last title name until 1982.
These events were the fall season finales of the Colgate Series, then later Toyota International Series circuits. They operated in much the same way as the men's WCT Circuit which also had seasonal WCT Finals held in the fall or winter.