The yellow floor tiles commonly installed in street corners, subway platforms and urban areas in general are one of the most pervasive and effective forms of accessibility design in the modern era (and it was under our noses all along). The subtlety and minimal obstruction of Seiichi's design made it an easy choice to install Tenji blocks all over the country, while their bumps and lines made them a necessity for those with impaired vision that wanted to move through cities independently. 

According to Curbed, "the first blocks were installed in the Japanese city of Okayama on March 18, 1967, next to a school for the blind. By the late 1970s, the blocks were in almost all of Japan’s railway platforms before eventually spreading abroad." The quick success of Tenji blocks provides a valuable lesson for the accessibility aids of the future: namely, that the best ideas are often easily integrated into what currently exists.