Brendan Bechtel, 35

On Sept. 1, Bechtel took the helm of his family’s century-old dynasty, one of the largest engineering and construction companies in the world (heard of the Hoover Dam or the Channel Tunnel?). The fifth-generation leader now commands one of the biggest privately held companies in the U.S., with $40 billion in 2015 revenue. It falls on Bechtel, formerly president and COO, to steer the company through challenges like a collapse in commodities prices and new competition from Chinese contractors. He’s been preparing for the role since 2010, but he has a lifetime of experiences to draw from: His first stint at a Bechtel construction camp was when he lived in a trailer in the jungle in Borneo while his father worked as a supervisor on a liquefied-natural-gas plant. He was 3 years old.

Read more about Bechtel in “Meet the Private Company That Has Changed the Face of the World.”