| GCat | Policy and Organization |
| MCat | General Reference |
| SCat | NAICS |
US Department of Labor Codes: Standard Industry Classification (SIC) and Standard Occupational Classification (SOC) Codes. North American Industry Classification Systems.
1997 NAICS and 1987 SIC Correspondence Tables [9967] 
Converts SIC codes into NAICS codes and vice versa
NAICS - North American Industry Classification Systems [393]
NAICS has replaced SIC industry classification
SIC - Standard Industry Classification Codes [1025]
Search engine for the 1987 US Department of Labor's SIC Code Manual
SOC - Standard Occupational Classification Documents [2996]
New occupational classification system that will include all jobs in the national economy (US)
Please report broken links by referencing the [number in brackets in grey].
Dictionaries
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