Marsh & McLennan Companies, Inc. MRSH

Company Overview

Marsh & McLennan Companies, Inc. is a global professional services firm operating primarily in the risk, insurance brokerage, reinsurance, health, wealth, and management consulting industries. The company advises corporate, government, and institutional clients on risk management, insurance placement, human capital strategy, and organizational performance. Its revenue is primarily fee-based and derived from advisory, brokerage, and consulting services rather than underwriting risk.

The firm traces its origins to 1871 with the founding of Marsh, later expanding through acquisitions and organic growth into a diversified professional services group. Over time, Marsh & McLennan evolved into a holding company structure with four globally recognized operating businesses—Marsh, Guy Carpenter, Mercer, and Oliver Wyman—each addressing distinct but complementary client needs. The company is widely regarded for its scale, data-driven advisory capabilities, and deep relationships with insurers, reinsurers, and multinational clients.