Atsushi Yoshida runs a 70-year-old firm specializing in high-voltage lightning arresters. Its devices, produced via research at the world's largest lightning-test facility, protect homes and infrastructure, as well as Japanese icons like Shinkansen bullet trains, the TOKYO SKYTREE and Kyoto's Kiyomizu-dera Temple, with a 70% domestic market share. Now Yoshida is taking this expertise to Rwanda, one of the world's most lightning-prone countries, conducting research and training local engineers.