Getty / Scott Olson
It's not hard to find startups led by 20-something founders in Silicon Valley.
But as the startups start to grow into multi-billion-dollar companies, even the most talented tech wunderkinds often need a seasoned executive partner who can provide "adult guidance" at some point down the road.
These 9 people were hired by some of the biggest tech companies to provide that type of counsel to a less experienced founder.