Grant Thornton International Ltd. is a global network of independently owned and managed accounting and consulting firms. They provide assurance, tax and specialist advisory services to public and private organizations. The U.S. firm, Grant Thornton LLP, based in Chicago, is the largest among them. The network has 521 offices in 113 countries.
Grant Thornton ranks No. 6 on Public Accounting Report's 2009 Top 100 list, behind RSM McGladrey and the Big Four. Grant Thornton LLP took second place in the Public Accounting Report's 2008 audit rankings behind Crowe Horwath.