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Metadata Encoding and Transmission Standard (METS) Official Web Site

METS Version 1 Namespace Page

This page contains information about the target namespace URI that identifies all Version 1 METS schemas. For information about the METS schema itself and its associated documentation see the METS Schema and Documentation page on the METS website.

The namespace identifier for METS Version 1 (all METS 1.x versions) is

METS schemas that use this namespace:

The lastest incremental release of the version 1 METS schema (i.e. 1.x for the highest value of x for which there is an official version--currently 1.8) will always be found at:


Backwards compatibility between version 1 METS schemas

In general all incremental Version 1 METS schemas are backwards compatible with previous version 1 schemas. The major exception to this rule occurred between the v.1.3 and v.1.4 schemas. In the version 1.4 schema the target namespace declared for XLink, which was erroneous in versions 1.1-1.3 of the schema, was corrected to "".

Future integral versions of the METS schema

Currently there are no definite plans for an integral version 2 series of the METS schema. A version 2 schema would only be implemented if changes were introduced which would break backwards compatibility with the version 1 schema series. If a version 2 schema were developed, it would be assigned a new target namespace (""); and the latest version of this schema series would reside at


The METS version 1 namespace URI "" may be resolved using HTTP content negotiation via the "Accept" HTTP request header. If a user agent requests "text/xml" (the standard MIME type for XML Schema), it will be HTTP 303 redirected to the current METS XML Schema. Otherwise, by default, it will be HTTP 303 redirected to this page with MIME type of "text/html"



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  July 1, 2011

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