North American Industry Classification System
You are here: Census.gov › Business & Industry › NAICS › History
History of NAICS - Early Development Documents
Issue Papers Relating to Industry Classification
- Issues Paper No. 1, "Conceptual Issues" [PDF, 3.78MB]
- Issues Paper No. 2, "Aggregation Stuctures and Heirarchies" [PDF, 1.92MB]
- Public Comments on Issues Papers No. 1 & 2 [PDF, 532KB]
- Issues Paper No. 3, "Collectability of Data" [PDF, 2.22MB]
- Issues Paper No. 4, "Criteria for Determining Industries" [PDF, 6.32MB]
- Issues Paper No. 5, "The Impact of Classification Revisions on Time Series" [PDF, 2.07MB]
- Issues Paper No. 6, "Services Classifications" [PDF, 1.34MB]
ECPC Concept Reports
- ECPC Report 1, "Economic Concepts in SIC Industries" [PDF, 47MB]
- ECPC Report 2, "The Heterogeneity Index: A Quantitative Tool to Support Industrial Classifications" [PDF, 15MB]
NAICS Clarification Memoranda, 1-3
[PDF] or 
denotes a file in Adobe’s Portable Document Format. To view the file, you will need the Adobe® Reader® 
available free from Adobe.
[Excel] or the letters [xls] indicate a document is in the Microsoft® Excel® Spreadsheet Format (XLS). To view the file, you will need the Microsoft® Excel® Viewer available for free from Microsoft®.
This symbol indicates a link to a non-government web site. Our linking to these sites does not constitute an endorsement of any products, services or the information found on them. Once you link to another site you are subject to the policies of the new site.
denotes a file in Adobe’s Portable Document Format. To view the file, you will need the Adobe® Reader® available free from Adobe.
[Excel] or the letters [xls] indicate a document is in the Microsoft® Excel® Spreadsheet Format (XLS). To view the file, you will need the Microsoft® Excel® Viewer available for free from Microsoft®.
This symbol indicates a link to a non-government web site. Our linking to these sites does not constitute an endorsement of any products, services or the information found on them. Once you link to another site you are subject to the policies of the new site.
Facebook
Twitter
Flickr
YouTube