In those early New York years, he found a home at La MaMa Experimental Theatre Club where he designed sets, costumes, lighting and props and developed theater productions that blended qualities of the Japanese avant-garde with his own spare aesthetic. He went on to work with noted theater directors Robert Wilson and Jerome Robbins on both national and international productions. He took painting classes at the Art Students League, where he would later teach, and encountered the work of many of the era’s innovators. Soon he was working in the studios of such notable painters as Larry Poons, Kenneth Noland and Helen Frankenthaler. For many years, Saito worked back and forth between theater and painting, the graceful movement, concise forms, and lighting qualities of the former greatly influencing the latter, and vice versa. Eventually, he turned solely to his studio practice where he honed his sophisticated compositions full of motifs and signs both real and imaginary, and his bold, unexpected use of color.

Through his teaching and in his studio, Saito supported and mentored a wide array of creative thinkers, many of whom today continue their practice in painting, writing, architecture and design.