The D-U-N-S Number is D&B’s unique, nine-digit, location-specific identifier, which D&B assigns as a means of identifying and tracking companies globally throughout their lifecycle. Once assigned, a D-U-N-S Number is neither reused nor assigned to another business. Used by the world's most influential standards-setting organisations, the D-U-N-S Number is recognised, recommended and/or required by more than 50 global, industry and trade associations, including the U.N, the European Commission and the U.S. central Government, where it is used by the General Services Administration, U.S. Postal Service and Department of Education, among others.