Kroll is credited with founding the modern corporate investigations industry.

He co-founded and serves as exexcutive chair of K2 Integrity (formerly K2 Intelligence).

• He founded of Kroll, Inc., which was sold to Marsh & McLennan in 2008, and co-founded Kroll Bond Rating Agency in 2010.

• In 2010, the Conference on Jewish Material Claims Against Germany engaged Kroll's services to investigate the theft of $42.5 million.

• Kroll is the father of comedian Nick Kroll.