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U.S. Federal Documents

Northwestern University Libraries have been a U.S. Federal Depository Library since 1876. Our collection includes materials in paper, microfiche, CD-ROM, DVD formats and online formats. This guide is based on a similar guide by Kelly Smith at UCSD.

Federal Depository Library Program

The Federal Depository Library Program (FDLP) was established by Congress to ensure that the American public has access to its Government's information. Since 1813, depository libraries have safeguarded the public's right to know by collecting, organizing, maintaining, preserving, and assisting users with information from the Federal Government. The FDLP provides Government information at no cost to designated depository libraries throughout the country and territories. These depository libraries, in turn, provide local, no-fee access to Government information in an impartial environment with professional assistance.

Northwestern University Libraries (NUL) was designated as a depository library in 1876.  Our federal collection is interdisciplinary with an emphasis on U.S. demographics, defense, business, economy, education, environment, public policy, legislation, health care, international trade, and foreign relations.  These items come in various formats, including print volumes, microfiche, CD, DVD, and online.

Most government publications are located in Room B190 on the lower level of the University Library. Some documents are housed offsite at the Oak Grove Library Center in Waukegan and may be requested using NUSearch for delivery to NU Libraries in Evanston or Chicago. Call numbers for government documents published after 1976 may be found by using NUSearch and many items may be checked out.  Since a significant proportion of the collection is not yet represented in NUSearch, contact library staff for assistance at

Logo for the Federal Depository Library Program

Other depository libraries in Chicagoland include the Chicago Public Library (Harold Washington Library Center), DePaul University, Illinois Institute of Technology, Loyola University Chicago, Northern Illinois University, Northeastern Illinois University, University of Chicago, and many others.


Collection Access & Locations

Public access to documents received through the Federal Depository Library Program (FDLP) is guaranteed by U.S. law. Please see the Library's policies covering Building Use, Public Computers, and Visitor Access for general information or assistance, contact with specific questions regarding the federal documents collection.

The majority of government publications at the NU Libraries are housed in the University Library, Lower Level, Room B190, which is not staffed.  Materials are in various formats, e.g. print, microfiche, CD, DVD, and VHS tapes.  Appointments for assistance can be made by contacting

Some government publications are stored off-site in the Oak Grove Library Center which will be indicated in, and can be requested using, NUSearch.

Call Numbers in the Government Collection

The Government & Geographic collections located in the University Library, Lower Level Room B190 are organized using several different call number systems.

Superintendent of Documents (SuDoc)

U.S. Federal government publications are arranged by the Superintendent of Documents (SuDocs) call number system. The SuDoc system is a provenance arrangement—publications are organized by the issuing agency. So, A call numbers are for the Department of Agriculture, C is Commerce, D is Defense, T is Treasury while TD is Transportation, and so on. There are, of course, exceptions to the straightforward assignment of letters: X and Y are used for publications from various Congressional committees and commissions.

SuDoc numbers do not read as a decimal, the way Dewey and Library of Congress (LC) numbers do. Instead, the numbers before and after the dot are whole numbers. So, while D 19.18 would come before D 19.3 in LC order (because it reads as 19 point one eight), it comes after D 19.3 in SuDocs order (because it reads as 19 point eighteen). See SuDocs Basics provided by Michigan State University Libraries for more guidance.

A very basic break-down of a SuDocs number:

  • I 49.10:999 
  • First letter indicates issuing department (I = Department of the Interior)
  • First whole number before the dot indicates a subordinate office within that department (49 = Fish & Wildlife Service)
  • First whole number after the dot indicates a category of publication, series, or serial title (10 = Directories)
  • Numbers or letters and numbers after the colon represent individual publications, years, issues or editions (pub date = 1999)

Dewey Decimal Call Numbers

Publications of the State of Illinois, the cities of Chicago or Evanston, or Cook County, reference works about maps and government information, and some atlases are classified with the Dewey Decimal call number system, which puts materials together by subject.

Library of Congress G Call Numbers

Flat maps in the locked map cases are organized using the Library of Congress G schedule. 

United Nations Document Symbols

NU Libraries uses the United Nations Document Symbols for organizing publications from UN agencies which we received in print and microfiche formats prior to 2012.

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Anne Zald
Anne Zald
Subjects: Government Information; Regulatory Compliance; Gender & Sexuality Studies
Northwestern University Library
1970 Campus Drive
Evanston, IL 60208
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