Marsh McLennan is a professional services company delivering advisory services and solutions across risk, strategy, and human capital. It operates through two core segments: Risk and Insurance Services and Consulting. The Risk and Insurance Services segment includes Marsh, an insurance broker, and Guy Carpenter, a specialist in risk and reinsurance. Its Consulting segment consists of Mercer, which provides human resources services, and Oliver Wyman, a management and economic consulting firm. Approximately half of the company’s revenue comes from markets outside the United States.