Werner Theunissen was a Dutch composer and lyricist of the 70s Dutch country music band "Pussycat". He rose to fame when his song "Mississippi", released by the band in 1975, became an international hit and sold an estimated 7 million copies worldwide.

Pussycat was a Dutch country and pop group led by the three Veldpaus-sisters: Toni, Betty, and Marianne. Other members of the band were guitarists Lou Willé, Theo Wetzels, Theo Coumans, and John Theunissen. Their song "Mississippi" was a #1 hit in most European countries, including the UK, in 1975/76.