While he asserted that "the poster isa mass-produced object that must have a commercial function" (Medlej), Cassandre found that he could use images, colors, and text in a sort of artistic fusion to grab the attention of the viewer. Making posters as large as 13' x 15', Cassandre learned how lucrative art could be (Owen). As Neil Harris observed, "business [could] beas stimulating a patron of the arts as prelates, cardinals, and popes were who represented the church in the fifteenth century."
Cassandre's approach was not without its detractors. There were those who wondered if his style would make its way from France into American advertising - specifically, whether the American advertising designers would be willing to set aside their more conservative and monotonous design styles for something that seemed to swing closer to the world of art than the world of business. Those who hoped that American advertisers would change their designs were those who saw how Cassandre's posters used geometry to grab the attention of the viewer; they realized the potential of "attention value." While advertising only attracts those whose "circumstances permit the possibility of action," Cassandre sought to make sure that the most focused attention would be on his posters (Parker). This focus would come with the elimination of distractions, so that the central message of the advertisement would be clear to the viewer (Parker).
Cassandre established a handful of principles in his poster design. As mentioned above, Cassandre aimed for very large posters, and had a revolutionary attitude toward text. While other poster-makers attempted to squeeze the text in around designs, or wherever it would fit, Cassandre found the text to be the central part of the poster, particularly in advertisements. He claimed that "design should be based on the text and not inversely" (Medlej). His emphasis on the artistic value of text led him to experiment widely in sans serif fonts (Megaw, Hatchings), even to invent the Peignot-font, which he believed to be a "purer form of the alphabet" as far as it expressed the "essential character of Roman letters" (Tam). His goal was to make Peignot one of the established text-faces, but this did not come about during his lifetime (Tam). Cassandre's emphasis on text even went to the use of alliterative slogans to increase the allure to the viewer (Hambourg).
Another one of his principles centerd around the use of geometry and architecture to design his posters. Enlarging a poster to the sizes that Cassandre wanted in the 1920's risked severe distortion of the original image, and so lines were used that would be difficult to distort. This use of line and form in a more figurative way was one of the basic influences in the later works of Max Lingner and Salvador Dali, who took the distortion of line and form to new frontiers (Held).
Cassandre's notions of poster-making had a significant effect on a variety of art forms throughout the rest of the twentieth century. His ideas concerning the use of line and color to increase audience attention became one of the founding tenets of the Bauhaus school.