USA Canada Latin America & the Caribbean Islands Union Catalogs in other continents

United Nations.
Name: United Nations System Shared Cataloguing and Public Access System
Link to Union Catalog.
Details: Union catalog of all the seperate libraries of the United Nations in New York, Paris, Vienna and Geneva.

World Bank and IMF.
Name: Global JOLIS Library Catalog
Link to Union Catalog.
Details: Union catalog of individual World Bank & IMF libraries around the world, (covers only libraries in countries that receive IMF or World Bank loans, grants, etc). Includes references to published IMF and World Bank materials, most of which have full text links.

OCLC
Name: OCLC FirstSearch WorldCat union catalog
Link to Union Catalog.
Details: Largest international global union catalog, part of OCLC's FirstSearch services. Contains records of 45,000 libraries in over 83 countries.
Access to WorldCat union catalog. Subscribers only.

UNESCO
Name: Networked Digital Library of Theses and Dissertations (NDLTD)
Link to Union Catalog.
Details: This group is an international organization dedicated to promoting the adoption, creation, use, dissemination and preservation of electronic analogues to the traditional paper-based theses and dissertations around the world. Sponsored by UNESCO and Adobe Systems. The union catalog lets you search and browse electronic theses and dissertations (ETDs), across multiple institutions around the world at once.

Project Gutenberg
Name: Project Gutenberg catalog
Link to Union Catalog.
Details: Project Gutenberg is the first and largest single collection of free electronic books, or eBooks whose copyright has expired. Over 10,000 eBooks are available in the catalog.

Union Catalogs in the Americas
Covering the U.S., Canada, Latin America and the Caribbean Islands.

U.S.A.
Name: Research Libraries Group union catalog
Link to Union Catalog.
Details: Union catalog of the major research and academic libraries in the U.S, Canada and Latin Amercia, and a great deal of libraries in Europe and the Asia-Pacific region, such as China, Russia, Australia, New Zealand, , Saudi Arabia, Japan. This explains why the RLG union catalog is available in over 400 languages, including Arabic, Chinese, Russian, Hebrew, Japanese, and Korean, and it is the second largest union catalog after OCLC's WorldCat. When you get to this link, click on "Online Databases" under "Products and Services menu", then on "RLG Union Catalog." N.B. free access (via the Eureka system) is available only on-site in major U.S. university libraries.
Access to RLG union catalog. Via Eureka. Subscribers only.

Name: Center for Research Libraries union catalog
Link to Union Catalog.
Details: Union catalog of the consortium of North American academic and independent research libraries. Mostly serials and dissertations.

Name: National Union Catalog of Manuscript Collections, NUCMC
Link to Union Catalog.
Details: Union catalog of records of archives and manuscript collections throughout the U.S. Based in Washington D.C.

Name: Military Education Research Library Network
Link to Union Catalog.
Details: Union catalog of military education libraries in the U.S. Includes the Pentagon's Department of Defense Regional Center libraries and their international counterpart libraries.

Name: ALADIN
Link to Union Catalog.
Details: Union catalog of university libraries in capital, Washington D.C. (metropolitan areas as well).

Below is a list of union catalogs for each of the 50 states in the U.S.

Name: MELVYL OPAC
Link to Union Catalog.
Details: Union catalog of all the seperate libraries of the University of California in the state of California. The combined total of these libraries is larger than the total collections in the Library of Congress!

Name: Pharos
Link to Union Catalog.
Details: Union catalog of the libraries in the 22 campuses of California State University.

Name: Link+
Link to Union Catalog.
Details: Union catalog of various public and academic libraries in states of California and Nevada.

Name: Monterey Bay Area Cooperative Library System, MOBAC
Link to Union Catalog.
Details: Union catalog of public, academic and special libraries in the counties of Monterey, San Benito and Santa Cruz on the California Central Coast.

Name: Prospector
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of Colorado.

Name: Colarado Virtual Library
Link to Union Catalog.
Details: Union catalog of libraries in the state of Colorado.

Name: reQuest
Link to Union Catalog.
Details: Union catalog of libraries in the state of Connecticut.

Name: Bibliomation
Link to Union Catalog.
Details: Union catalog of public and school libraries in the state of Connecticut.

Name: HOLLINET, KentNet, TIPCAT Consortium
Link to Union Catalog.
Details: Union catalog of public libraries in the state of Delaware.

Name: SunLine
Link to Union Catalog.
Details: Union catalog of libraries in the state of Florida.

Name: SunLink
Link to Union Catalog.
Details: Union catalog of K-12 public schools libraries in the state of Florida.

Name: LINCCWeb
Link to Union Catalog.
Details: Union catalog of community college libraries in the state of Florida.

Name: HSPLS
Link to Union Catalog.
Details: Union catalog of libraries in the state of Hawaii.

Name: ILLINET
Link to Union Catalog.
Details: Union catalog of libraries in the state of Illinois.

Name: Virtual Illinois Catalog / Statewide Illinois Library Catalog
Link to Union Catalog.
Details: Union catalog of libraries in the state of Illinois, via OCLC's WorldCat interface.

Name: PALNI
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of Indiana.

Name: SILO
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of Iowa.

Name: Kansas union catalog
Link to Union Catalog.
Details: Union catalog of libraries in the state of Kansas.

Name: KVL
Link to Union Catalog.
Details: Union catalog of libraries in the state of Kentucky.

Name: LOUISiana Union Catalog
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of Louisiana.

Name: Maine Info Net
Link to Union Catalog.
Details: Union catalog of libraries in the state of Maine

Name: Merrimack Valley Library Consortium Union Catalog
Link to Union Catalog.
Details: Union catalog of public libraries in the central parts of the state of Massachusetts.

Name: MiLE
Link to Union Catalog.
Details: Union catalog of academic libraries the state of Michigan.

Name: MOBIUS
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of Missouri.

Name: MnLink
Link to Union Catalog.
Details: Union catalog of libraries the state of Minnesota.

Name: PALS
Link to Union Catalog.
Details: Union catalog of all the academic libraries in the state of Minnesota.

Name: CLIC
Link to Union Catalog.
Details: Union catalog of CLIC consortium libraries in the state of Minnesota.

Name: Montana Library Network
Link to Union Catalog.
Details: Union catalog libraries in the state of Montana.

Name: Link+
Link to Union Catalog.
Details: Union catalog of various public and academic libraries in state of Nevada.

Name: NELLCO Catalog
Link to Union Catalog.
Details: Union catalog of law libraries in New England.

Name: NHU-PAC
Link to Union Catalog.
Details: Union catalog of law libraries in the state of New Hampshire.

Name: JerseyCat
Link to Union Catalog.
Details: Union catalog of libraries in the state of New Jersey.

Name: RALLY
Link to Union Catalog.
Details: Union catalog of some major libraries in the state of New Mexico.

Name: Connect NY
Link to Union Catalog.
Details: Union catalog of major academic libraries in the state of New York.

Name: Union Catalogs in Western New York
Link to Union Catalog.
Details: Union catalog of libraries in the western part of the state of New York.

Name: CaDiLaC
Link to Union Catalog.
Details: Union catalog of libraries in the eastern part of the state of New York.

Name: SEAL
Link to Union Catalog.
Details: Union catalog of libraries in the southeastern part of the state of New York.

Name: ICEPAC
Link to Union Catalog.
Details: Union catalog of libraries in the northern part of the state of New York.

Name: Rally Cat
Link to Union Catalog.
Details: Union catalog of libraries in RRLC network in Rochester in the state of New York.

Name: Roaring Cat
Link to Union Catalog.
Details: Union catalog of academic, public and special libraries (as well as many healthcare, corporate, and museum libraries) in Rochester in the state of New York.

Name: CNCRL
Link to Union Catalog.
Details: Union catalog of major libraries in the state of North Carolina.

Name: ODIN
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of North Dakota.

Name: OhioLINK
Link to Union Catalog.
Details: Union catalog of libraries in the state of Ohio.

Name: ODOL
Link to Union Catalog.
Details: Union catalog of libraries in the state of Oklahoma.

Name: SUMMIT
Link to Union Catalog.
Details: Union catalog of the academic libraries in the states of Oregon and Washington.

Name: EZ-Borrow Pennsylvania Academic Library Consortium
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of Pennsylvania.

Name: AccessPA
Link to Union Catalog.
Details: Union catalog of major libraries in the state of Pennsylvania.

Name: InRhode Library Cat
Link to Union Catalog.
Details: Union catalog of academic libraries in the state of Rhode Island.

Name: SDLN
Link to Union Catalog.
Details: Union catalog of libraries in the state of South Dakota.

Name: Utah's Catalog
Link to Union Catalog.
Details: Union catalog of public and academic libraries in the state of Utah.

Name: Vermont Department of Libraries Catalog
Link to Union Catalog.
Details: Union catalog of libraries in the state of Vermont.

Name: SUMMIT
Link to Union Catalog.
Details: Union catalog of the academic libraries in the state of Washington.

Name: WVLC
Link to Union Catalog.
Details: Union catalog of public and high school libraries in the state of West Virginia.

Name: WISCAT
Link to Union Catalog.
Details: Union catalog of libraries in the state of Wisconsin.

Name: WYLDCAT
Link to Union Catalog.
Details: Union catalog of libraries in the state of Wyoming.

Canada
Name: Virtual Canadian Union Catalogue or vCuc
Link to Union Catalog.
Details: Union catalog providing a single point of access and uniform interface to collections held by major Canadian libraries.

Name: AMICUS
Link to Union Catalog.
Details: Union catalog comprising the National Library of Canada as well as the holdings of 1,300 Canadian libraries.

Name: Canadian Consortia and Regional Catalogues
Link to Union Catalog.
Details: Union catalogs for all public and university libraries for each of the provinces in Canada, viz Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan, and Yukon.

Latin America

Link to Union Catalog.
Details: Union catalogs for libraries the following Central American countries: Mexico, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica and Panama. The union catalog called Meta Base provides access to the bibliographical data of diverse libraries and centers of documentation in the region.

Brazil
Name: Rede Cooperativa de Bibliotecas Brasileiras
Link to Union Catalog.
Details: Union catalog comprising libraries in Brazil.

Mexico
Name: Catálogo de Libros (Librunam)
Link to Union Catalog.
Details: Union catalog comprising special and university libraries in Mexico.

Name: HELA
Link to Union Catalog.
Details: Union catalog of the serials collection in university libraries in Mexico, as well as major Latin American countries.

Argentina
Name: Catálogo Colectivo (Red de Redes de Información Económica y Social UNIRED)
Link to Union Catalog.
Details: Union catalog comprising government, special and university libraries in Argentina.

Venezuela

Uruguay
Name: Catálogo Colectivo de Publicaciones Seriadas Universidad de la República
Link to Union Catalog.
Details: Union catalog serials in university libraries in Uruguay.

Peru
Name: Oficina General del Sistema de Bibliotecas y Biblioteca Central
Link to Union Catalog.
Details: Union catalog comprising special and university libraries in Peru.