Deloitte is one of the "Big Four" global accounting and consulting firms, with over 220,000 professionals providing audit, consulting, tax, and advisory services in more than 150 countries. It has a long history dating back to 1845 and is the largest private professional services network in the world. Deloitte focuses on creating value for clients through industry-leading services in areas like consulting, audit, tax, and risk management. Its vision is to be the standard of excellence through high quality work, inclusion, collaboration, and opportunity.