Poul Kjærholm had a particular interest in different construction materials; especially steel which he considered a natural material with the same artistic fineness as other natural materials. Poul Kjærholm was employed at Fritz Hansen for about a year, where he designed a number of noteworthy chair prototypes. In 1955 Poul Kjærholm initiated his collaboration with manufacturer Ejvind Kold Christensen, which lasted until Poul Kjærholm's death in 1980. In 1982, Fritz Hansen took over the production and sales of "The Kjærholm Collection", developed from 1951 to 1967.