Government Documents are organized by the Superintendent of Documents Classification System, which is designed to group publications by government agency or organization.
Each SuDoc number has two distinguishing elements: a letter or letters at the beginning and a colon in the middle. The part of the number through the colon is called its stem.
The stem begins with the letter or letters designating the agency issuing the document.
stem Name of agency A Department of Agriculture TD Department of Transportation
Offices or divisions within the agency are given a number.
stem office or
division numberName of office or division A 13 Forest Service A 77 Agricultural Research Service A 98 Food and Nutrition Service This number is followed by a point. The number following the point identifies the various series of publications issued.
Closely related series may be attached by a slash, and then further, a hyphen.A 13.1 Annual reportA 13.28 Maps and charts
A 13.78 Research papers
The number and/or letters following the colon uniquely identify each individual item.A 13.80 Resource BulletinsA 13.80/5 Pulpwood Production in the North Central Region by County
A 13.80/5-2 Pulpwood Production in the Lake States
Annual publications, such as reports and statistics include a number indicating the year.
Many government publications are issued in numbered series.A 1.47:999 Agricultural Statistics, 1999With periodicals, such as Agricultural Research, the number following the colon indicates the volume and number separated by a slash.A 1.77:86 Home and Garden BulletinUnnumbered publications are assigned a number based on the principal subject word of the title, similar to the Dewey Decimal Classification System cutter number.A 77.12:47/6 Agricultural Research, Vol. 47, No. 6Again, there may be numbers after a slash indicating series, edition or year.A 13.2:At 6/2 Forest Atlas of the SouthA 77.40:C 18 Compendium of Animal Resources
A 98.2:Sn 1 Summertime Snacks
Items are shelved first by the stem:
Alphabetically by letter
Then numerically by the number before the point
Then numerically by the number after the point
Then numerically by any numbers after a slash or dashItems with the same stem are then shelved by the individual item number following the colon.
Numbers following the colon come before letters
Then alphabetically by letter
Then numerically by numberUnlike the Dewey Decimal Classification System, each number -- before the point, after the point, after the slash/dash, or after the colon -- is a whole number and shelved in counting order.
1 ... 2 ... 3 ... 10 ... 20 ... 30 ... 100 ... 200 ... 300 ... 1000 ... 2000 ... 3000
Materials are arranged to the left along the outside walls, and then on the middle shelves, starting with the range closest to the door.
Current major agency designations are listed below. The complete List of Classes, published quarterly by the Superintendent of Documents, is available from the Government Documents Librarian and on the Internet at the Documents Data Miner.
A more detailed explanation of SuDoc Classification is available on the Internet at the Federal Depository Library Program Administration site.
Major Agency Designations