is a Japanese industrial designer who known as the designer of Nissan's pike car series with its retro-future design. Currently, he is a professor of Keio University Shonan Fujisawa Campus (SFC), a guest design director for au, and the manager of his own company, waterdesign. He has collaborated with companies such as Nissan, Suzuki, Toyota (WiLL), Olympus, KDDI, and Cassina.
The S Cargo was not designed by Sakai. Sakai led the Pike designs and created a proposal for the Nissan Figaro, but the design selected for final production (first shown at the 1989 Tokyo Motor Show) was designed by Nissan's in-house design team, led by Jim Shimizu (Shimizu Jun).