Arthur J. Gallagher & Co. is an insurance brokerage and risk management services company based in Rolling Meadows, Illinois, a suburb of Chicago. The company provides insurance brokerage and risk management services, which primarily includes processing of workers compensation and automobile insurance claims via the company's adjusters. The company is ranked 367th on the Fortune 500 and 192nd on the Forbes Global 2000. Founded in 1927, the company ranks among the world's largest insurance brokers. Wikipedia