The exhibition gives a survey on Bærtling's oeuvre and traces his artistic development in exemplary works. With works mainly from the 1950s the show is in particular focusing on Bærtling's principle of the "Open Form" as well as his experiments with the constructivist pictorial language. Before experimenting with abstraction in the 1940s the self-taught artist had begun as a figurative painter. He was influenced by Henri Matisse and studied with Fernand Léger. Bærtling didn't conceptualize or construct his pictures in advance, but painted intuitively and freehand. Especially important for his work were Auguste Herbin's two-dimensional, flat compositions. The French painter Herbin had started at the end of the 1930s to produce concrete paintings based on strict principles of flatness and simple geometric forms. Bærtling himself had fundamental influence on Günter Frutrunk's development as a painter.

Each period of Bærtling's oeuvre is characterized by typical forms and colours and thus proves the artist's systematic and meticulous exploration of painting. For instance the canvases of the 1950s are known for it's dynamic forms, colours and a particular size. In the 1960s the artist focused on the colours black, purple and his peculiar greenish white. Monumentality, red and magenta tones characterize the paintings of the 1970s. In addition to works from these decades we present paintings from his last period, such as the last canvas the artist painted before he died in 1981. Bærtling's practice as a sculptor will be presented in the show with the work "Yayan" from 1971. The sculpture is an example for his dynamic constructions of rods of black steel, where the linear elements of his paintings seem to have acquired a life of their own.