Deloitte is an Anglo-American multinational professional services network. Deloitte is one of the Big Four accounting organizations and the largest professional services network in the world by revenue and number of professionals, with headquarters in London, England. “Deloitte” is the brand under which tens of thousands of dedicated professionals in independent firms throughout the world collaborate to provide audit & assurance, consulting, risk and financial advisory, risk management, tax, and related services to select clients.