Kai Kristiansen, born in 1929, is a Danish designer, known for making furniture in the Danish Modern Style. Like many designers of his generation, he apprenticed in cabinet making before enrolling, around 1948, at the Royal Danish Academy of Fine Arts in Copenhagen under the highly influential designer Kaare Klint (see below).

In 1955, at the age of 26, Kristiansen opened his own studio, going on to create beautifully crafted, human-centred furniture, in the style that became known as Danish Modern (see below). Working in oak, teak, and rosewood, he designed popular, pioneering pieces including the FM Wall Unit, Model 42 Chair, Model 31 Chair, and Ep401 Desk, produced by well-known furniture manufacturers such as Fornem Møbelkunst, Fritz Hansen, Feldballes Møbelfabrik, Vildbjerg Møbelfabrik, and Magnus Olesen.

Kai Kristiansen’s success continues today, both with the popularity of his classic designs and with new collaborations and creations. In 2014, he collaborated with the Miyazaki Chair Company in Japan, reimagining some of his classic designs to create the Handy Chair, 4110 Chair, and Paper Knife seating collection. In 2016, he worked with Great Dane Furniture, to reissue his designs popularised in the 1950s.

The modular FM Reolsystem Wall Unit was first produced in 1957 for Feldballe Møbelfabrik. It was a success throughout Scandinavia and beyond, reaching through Europe and over the Atlantic to the United States of America.