OCLC, a global library cooperative, supports thousands of libraries in making information more accessible and more useful to people around the world. We provide shared technology services, original research and community programs that help libraries meet the ever-evolving needs of their users, institutions and communities.

Because what is known must be shared.®

1967 as a nonprofit, member-driven library community

16,131 in 120 countries

Library types served
Research, academic, public, school, medical, law, corporate, government, special, state and national libraries, groups and consortia

Major services
Library management, discovery, cataloging, digital libraries, virtual reference, resource sharing


  • WorldCat.org
  • WorldCat Discovery
  • WorldShare Management Services
  • EZProxy
  • OCLC Cataloging and Metadata Subscription
  • WorldShare Interlibrary Loan
  • Dewey Services



Provide library visibility on the Web.

The Internet is the first choice for most information seekers. With your holdings and other metadata contributed to WorldCat, WorldCat.org makes your library's resources more visible to more people on the Web. As the world's largest library catalog, it helps users find items in libraries close to them. So your reliable, verified information and personal assistance—the hallmarks of the library experience—gain greater exposure, credibility and use among people in your community and around the world.



Share your library's holdings across the Web

Information about your library's holdings and online services is actively spread across the Web via strategic partnerships with key sites such as Google and Goodreads as well as by social and distributed Web technologies such as APIs, widgets and mobile and social apps that appeal to users, other information providers and e-businesses.

The result? Your local resources gain a global presence, become part of people's normal Web workflow and get in front of the increasing number of people who rely almost exclusively on the Internet.


WorldCat Discovery

Search WorldCat, the world’s most comprehensive library database

Identify resources at your library and in the collections of the world’s libraries. Library users and staff use WorldCat Discovery to search the WorldCat database of electronic, digital and physical resources; to identify materials they need and to find out where they are available.

You can discover more than 2.8 billion electronic, digital and physical resources with access to WorldCat and a central index that represents 2,461 e-content collections from providers such as Gale, ProQuest, Elsevier, Springer and others.



Build, showcase and preserve your digital collections

CONTENTdm allows you to easily build and showcase your digital collections on your personalized website, making them more discoverable to people around the world. CONTENTdm also secures and monitors your master files in a cloud-based preservation archive so they remain safe for the future.

With integrated tools, you can quickly create a branded look and feel for your library's digital collections website. CONTENTdm makes it easy to customize your site, whether or not you have programming skills.

The WorldCat Digital Collection Gateway is a free, self-service tool that's integrated with CONTENTdm. Upload your collection metadata to WorldCat—the premier database of library materials. From there, students and scholars can find their way to your local digital collections from WorldCat.org, WorldCat Discovery Services and many OCLC partner services.


WorldShare Management Services

Save time and money. Improve service to users.

Faced with scarce resources, changing user needs and increasingly diverse collections and systems, libraries are looking for new ways to save time and money while improving service to their users. By sharing data and work across many member libraries, WorldShare Management Services (WMS) offer libraries cost savings, workflow efficiencies and the ability to deliver new value to users.

With WorldCat® data as its foundation, libraries using WMS experience improved workflows and a drastic reduction in the time it takes to perform routine tasks, including e-resource management and cataloging. They have also been able to reallocate full-time staff to undertake new initiatives, such as cataloging special collections, creating LibGuides for users and redesigning library websites.

What's included:




Connect your users to e-content with a single sign-on.

Authentication is an important issue for libraries and information seekers; certain library resources require authorized access, while remote information seekers want access without obstacles. EZproxy access and authentication software connects to many content providers, including OCLC, EBSCO, Gale and others. It also connects to a wide variety of authentication services, including LDAP, SIP and Shibboleth, which reduces the number of authorizations and passwords users need to remember. Users gain secure remote access to the Web-based, licensed content they discover in libraries.


OCLC Cataloging and Metadata Subscription

Save time with streamlined cataloging.

Benefit from the ongoing work and expertise of OCLC and member libraries worldwide that continue to collectively create, enhance and share quality records found in WorldCat®. Unlimited access to WorldCat allows you to quickly find the records you need so you can copy catalog from one source instead of doing original cataloging. Plus, when improvements that you care about are made to a WorldCat record, OCLC will automatically send you MARC record updates to improve the discoverability of your collections.

Access a comprehensive suite of metadata management tools and services (including free training and support) to efficiently manage all of your print and electronic resources. Quickly optimize your cataloging workflows while reducing operational costs with expert tools and services that fully support both RDA and AACR2 standards.


WorldShare Interlibrary Loan

Automate interlibrary loan staff workflows and help your users quickly get the resources they need.

In the face of a limited budget, reach out to the largest cooperative of resource-sharing libraries in the world to supply your users with the resources they need. WorldShare Interlibrary Loan connects you to thousands of libraries whose entire collections can be viewed at a glance in WorldCat®. Together, these libraries have created a shared, global library collection for the benefit of all library users.

With a manual process for ILL tasks, you spend a lot of time in one-on-one conversations with other libraries to fulfill requests. WorldShare ILL simplifies your processes by showing you other libraries’ holdings, policies and fees before you make a request. When one library can’t fulfill a request, it’s automatically routed to the next library you identified. In addition, WorldShare ILL is simple to learn and teach to staff. You can set up your library’s policies and other standard information in advance to make sure it’s correctly included on every request.


Dewey Services

Organize your materials with the world's most widely used library classification system.

Libraries big and small the world over use the Dewey Decimal Classification (DDC) system to help make sense of today's complex library collections. The DDC is available in both print and Web formats and in full and abridged editions.

The Dewey Decimal Classification (DDC) system is the world’s most widely used way to organize library collections. The DDC constantly updates to enable better discovery across any topic in multiple languages. Because the DDC is easy to use, you can increase the visibility of your materials quickly and efficiently.

For purchase, subscription and trial requests and questions and enquiries, we kindly ask you to contact ITSN.

ITSN is the sole authorized distributor of OCLC services and databases in Turkey, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan.

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