Arthur J. Gallagher & Co. is one of the world's largest insurance brokerage and risk management services firms. The company operates primarily through two main segments: Brokerage and Risk Management. The Brokerage segment, which accounts for the vast majority of the company's revenue (approximately 86% in 2024), involves negotiating and placing property/casualty insurance, employer-provided health and welfare, and retirement products. This segment also provides specialized consulting services in areas such as employee benefits, human resources, and compensation. The Risk Management segment (approximately 14% of 2024 revenue), operating primarily under the Gallagher Bassett brand, provides contract claims settlement and administration services for enterprises that choose to self-insure their property/casualty coverages, as well as for insurance companies.
Geographically, Gallagher has a massive global footprint, operating in around 130 countries through a combination of direct operations and a network of correspondent brokers and consultants. The company has grown significantly through a disciplined strategy of organic growth and aggressive mergers and acquisitions, completing hundreds of tuck-in acquisitions to expand its specialty capabilities and geographic reach. Its competitive position is bolstered by its scale, specialized industry expertise, and comprehensive suite of risk transfer and advisory solutions, making it a top-tier player alongside peers like Marsh McLennan and Aon.
