From 1969 Poul Christiansen worked as a freelance designer creating lamps for the Danish lighting company Le Klint. In 1973 he graduated from the School of Architecture at the Royal Academy of Fine Arts in Copenhagen. Four years later he was employed by Ib and Jørgen Rasmussen where he stayed until 1986 making architecture and design for Kevi and Herman Miller. During the 1980’s Christiansen also designed for Sorø Stolefabrik in Denmark, Lübke and Brunner in Germany and worked for Penta Design (Computerized working place for the Danish Post and Telegraph).
In 1987 Christiansen founded the design studio Komplot Design together with the Russian-Danish designer Boris Berlin.
In 1983 Berlin moved to Denmark where he founded Boris Berlin Design Studio, and from 1985 to -87 he worked for Penta Design where he made a computerized workstation for the Danish Post and Telegraph. In 1987 Berlin founded the design studio Komplot together with Danish architect Poul Christiansen, working with furniture design for clients such as Norwegian ForaForm, Swedish Klaessons and Danish Gubi.
The Kompot studio has received several design awards and are represented at museums all over the world. One of their most prolific object is the chair Non, designed for the Swedish manufacturer Källemo in year 2000. Non was made of hard rubber-like polyeurethan foam on a steel frame, that made it flexible and allowed it to be used outdoors as well as indoors. Another cornerstone for the Komplot Studio is the Gubi Chair, with a seat shell made in the 3D- laminated veneer technique. It was designed for the Danish company Gubi in 2003.
From the 1980s Christiansen and Berlin have participated annually in Scandinavian furniture fairs as well as fairs in Milan, Cologne and Tokyo. They have also been represented in several exhibitions in Denmark and abroad such as Designs of the year at the Design Museum in London in 2008. In March 2015 Komplot Design was awarded The Thorvald Bindesbøll Medal by the Royal Danish Academy of Fine Arts for excellence in the fields of applied art and industrial design.
For the Dry Chair for the producer Luminaire Christiansen was awarded the German Design Award Excellent product design in 2020. Poul Christiansen is represented as a furniture designer in among others the collections of The Danish Art Foundation in Copenhagen, the Museum of Modern Art in New York and Designmuseo in Helsinki.