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Manage your name with identifiers

Persistent identifiers ensure that online references remain accessible in the future. Persistent identifiers can be assigned both to digital objects, such as data or publications, and to persons.

Online resources can generally be accessed by making use of a web address or a URL. Such web addresses may change, however, for a number of different reasons. The name of a server may change, web resources may be migrated to different systems, or the filenames of objects can change. When URLs of objects change, the original references to these objects often cease to function correctly. As has been shown in a number of studies, such as 'The decay and failures of web references', more than half of the online resources used as references in academic publications can no longer be accessed after a period of nine years.

The problem that URLs do not offer permanent access to resources can be addressed relatively easily by making use of persistent identifiers (PIDs). They are permanent codes which can continue to refer to online resources, even when their URLs change. A PID is managed by an organisation that links a persistent identification code with the most recent URL. This association is updated whenever the URL changes. Different PID systems are currently in use. Well-known examples include the Handle, URN/NBN and the DOI.


Academic journals often assign DOIs to publications. DOIs are used increasingly by repositories, to refer to objects and to metadata. DOI has been an ISO standard since 2012. In the Netherlands, DOIs are managed by DataCite Netherlands.

Persistent identifiers can be assigned both to digital objects and to persons. One example of an identifier system for persons is the ORCID.


Open Researcher en Contributor Identifier (ORCID) is an international system for the persistent identification of academic authors. ORCID is managed by an international consortium consisting of universities, national libraries, research institutes and data repositories.

At present, publications, research data and associated metadata are often stored in different bibliographical systems. It is often difficult to connect these resources correctly. One of the main reasons for this is that there is often some confusion about the identity of authors. Author names may change, and they are not always unique. In many cases, we can only refer reliably to persons when we make use of unique and persistent numbers. ORCID has emerged as one of the main systems for identifying researchers.

This video provides ashort explanation of ORCID and its advantages

ORCID is demanded increasingly by academic publishers and by funders, such as the Horizon2020 programme. When publications and research data are associated with an ORCID id, the information about these resources can effectively be exchanged across databases, across countries and across academic disciplines.

Importantly, you always retain full control over your own ORCID id. Initially, you need to request your own ORCID id, and you are also responsible for the information that is associated with this identifier. You can easily indicate which information can be public, and which information needs to remain private.

More information

For more information, and for more discussions about the benefits of ORCID, please visit The Connected Leiden Researchers. http://connectedleidenresearcher.nl/