Between 1918 and 1921 Schleger studied at the Kunstgewerbeschule in Berlin. He began his career as a publicity and set designer for John Hagenbeck Films. In 1924 he moved to New York where he stayed for five years, establishing his Madison Avenue studio and using the pseudonym ‘Zero’. He then returned to Berlin in 1929 and worked at the German office of London ad agency Crawford’s. In 1932 he moved to England and freelanced for major British commercial and industrial corporations, designing posters for Shell-Mex and BP, the wartime ministries, GPO and London Transport, for whom he designed bus stop signs, simplifying the existing circle-and-bar symbol. Between 1950–62, he worked for the advertising agency Mather and Crowther. Zero’s studio became Hans Schleger and Associates in 1953. Schleger was involved in unifying design policies and pioneering the concept of corporate identity for clients like Mac Fisheries, Fisons, British Rail and British Sugar Corporation.