Stażewski was the pioneer of the classical Avant-garde of the 20s and 30s; representative of the Constructivist movement; co-creator of the Geometric Abstract art movement of the 60s, 70s, and 80s; creator of reliefs, designer of interiors, stage scenery, and posters.
Stażewski studied under Professor Stanisław Lentz at Warsaw's Szkoła Sztuk Pieknych (School of Fine Arts) between 1913 and 1919. He joined the first-ever Polish avant-garde group created in 1917, which was initially referred to as the Polish Expressionists and renamed itself the Formists in 1919. Stażewski debuted in 1920, showing his works with the Formists at the Towarzystwo Zachęty Sztuk Pieknych (Society for the Encouragement of the Fine Arts) in Warsaw. In 1921 he presented his paintings along with Mieczyslaw Szczuka at the avant-garde Polish Artistic Club. In 1922, Stażewski participated in the Formists' F 9 exhibition at the Salon of Czesław Garliński in Warsaw. In 1923 he participated in the Exhibition of New Art in Vilnius and the International Exhibition of New Art in Łódź. These two events effectively initiated the Constructivist movement in Poland. Stażewski was a founding member of the Grupa Kubistow, Konstruktywistow i Suprematystow Blok (Block Group of Cubists, Constructivists, and Suprematists) (1924-1926) and other groups which built on the Block program, including Praesens (1926-29) and a.r. group (1929-1936). Stażewski also participated in editing the magazines Block i Praesens.
Beginning in 1926 Stażewski represented Polish art abroad in exhibitions organized by the Towarzystwo Szerzenia Sztuki Polskiej wśród Obcych (Society for the Propagation of Polish Art Among Foreigners). In 1928 he designed the covers of MUBA magazine, produced in Paris by the Lithuanian poet Juozas Tysliava; also, as an extension of his Parisian activities, in 1929 he began working with Jan Brzękowski and Wanda Chodasiewicz-Grabowska in publishing the magazine L'Art Contemporain