Mainly autodidact, and employed at the Savoy Company as a graphic designer, Bortnyik met Kassák in 1917 and became a member of avant-garde newspaper MA (Today) first in Hungary and later in Vienna. He developed his own style called picture-architecture – considered the Hungarian answer to Constructivism. In 1925 he moved to Weimar: he was influenced by Bauhaus and found his own advertising studio. Back in Budapest he managed the avant-garde theatre Green Donkey and found the art school Műhely, while taking on some commercial work. After WWII he turned to political posters: he became editor of Free Art magazine and director of the University of Fine Arts.