Mark Ritsema is a singer, guitarist, songwriter, from the Netherlands, based in Rotterdam.

During the eighties and nineties he fronted cult bands Spasmodique and Cobraz. In the 00’s he played with Raskolnikov and currently he is working with Spasmodique and Polar Twins, both on an new album. He also performed as the solo artist Nightporter and plays guitar for John Sinclair, Vera and Mecano.