Kroll, LLC, formerly Duff & Phelps LLC, is an American multinational financial consultancy firm based in New York City. It was founded as Duff & Phelps in 1932 by William Duff and George Phelps. Since then, the firm has added more than 30 complementary companies to its portfolio, including the acquisition of Kroll Inc. in 2018. Duff & Phelps decided to start rebranding itself using the Kroll name in 2021, and it completed the renaming process in February 2022.