Four primary IRS Divisions at-a-glance: Large Business and International Small Business/Self-Employed Tax-Exempt and Government Entities Wage and Investment Other principal offices: Appeals Communications and Liaison Criminal Investigation Equity, Diversity and Inclusion Office of Chief Counsel Office of Fraud Enforcement At-a-Glance Office of Professional Responsibility (OPR) Office of Promoter Investigations Privacy, Governmental Liaison and Disclosure Procurement Return Preparer Office Taxpayer Experience Office Whistleblower Office