The 2000 Standard Occupational Classification (SOC) system is used by U.S. federal statistical agencies to classify workers into occupational categories for the purpose of collecting, calculating, or disseminating data. All workers are classified into one of more than 820 occupations according to their occupational definition. The United Nations administers the International Standard Industrial Classification of all Economic Activities (ISIC) and national classifications tend to relate to this global initiative. In the European Union, since 1990, members states have been obliged to conform to Standard Industrial Classification (SIC92).
Source: Staffing Industry Analysts