High Quality Content by WIKIPEDIA articles! Oliver Wyman is an international management consulting firm. Founded in 1984, the firm adopted its current form in May 2007, when Mercer Oliver Wyman joined with Mercer Management Consulting and Mercer Delta to become one firm named Oliver Wyman. Oliver Wyman is headquartered in New York City with 50+ offices in Americas, Europe and Asia Pacific and employs over 3,000 professionals. It is part of the Oliver Wyman Group, which is a business unit of Marsh & McLennan.