Statistics Denmark follows the international classifications of statistics.
National Accounts and Foreign Trade - Eurostat
For Eurostats list of classifications related to national accounts (NACE) and foreign trade (CN-the Combined Nomenclature) please consult the RAMON Metadata Server
Foreign Trade and Industry- United Nations
The United Nations maintains a number of economic and social classifications.
Among those are SITC (Standard International Trade Classification), ISIC (International Standard Industrial Classification of All Economic Activities), and the CPC (Central Product Classification).
A list of these classifications is available at:
United Nations Statistics Division
The International Standard Classification of Education as defined by: