The TEI was established in 1987 to develop, maintain, and promulgate hardware- and software-independent methods for encoding humanities data in electronic form. Over nearly three decades the TEI has been extraordinarily successful at achieving its objective and it is now widely used by scholarly projects and libraries around the world.
When the Text Encoding Initiative (TEI) was originally established, scholarly projects and libraries attempting to take advantage of digital technology seemed to be faced with an overwhelming obstacle to creating sustainable and shareable archives and tools: the proliferating systems for representing textual material. These systems seemed almost always to be incompatible, often poorly designed, and multiplying at nearly the same rapid rate as the electronic text projects themselves. This situation was inhibiting the development of the full potential of computers to support humanistic inquiry by erecting barriers to access, creating new problems for preservation, making the sharing of data (and theories) difficult, and making the development of common tools impractical.
In November 1987 a meeting at Vassar College was convened to address these problems. Sponsored by the Association for Computers in the Humanities and funded by the National Endowment for the Humanities, it brought together a diverse group of scholars from many different disciplines and representing leading professional societies, libraries, archives, and projects in a number of countries in Europe, North America, and Asia. At this meeting the intellectual foundation for Text Encoding Initiative was articulated. The organization of the actual work of developing the TEI Guidelines was then undertaken by the three TEI sponsoring organizations: The Association for Computers in the Humanities, the Association for Literary and Linguistic Computing, and the Association for Computational Linguistics.
The initial phase resulted in the release of the first draft (known as "P1") of the Guidelines in June 1990. A second phase, involving an additional 15 working groups making revisions and extensions, immediately began and released its results throughout 1990–1993. Then, after another round of revisions, extensions, and supplements, the first official version of the Guidelines (‘P3’) was released in May 1994. Early on in this process a number of leading humanities textbase projects adopted the Guidelines — while they were still very much a moving target of rapidly changing drafts — as their encoding scheme, identifying problems and needs and contributing proposed solutions. In addition, workshops and seminars were conducted to introduce the wider community to the Guidelines and ensure a steady source of experience to support continuing development. As more scholars became acquainted with the Guidelines, comments, corrections, and requests for extensions arrived from around the world. In the end there were nearly 200 scholars from many disciplines, professions, and countries in the core group that was developing the TEI Guidelines.
The impact of the TEI on digital scholarship has been enormous. Today, the TEI is internationally recognized as a critically important tool, both for the long-term preservation of electronic data, and as a means of supporting effective usage of such data in many subject areas. It is the encoding scheme of choice for the production of critical and scholarly editions of literary texts, for scholarly reference works and large linguistic corpora, and for the management and production of detailed metadata associated with electronic text and cultural heritage collections of many types.
The TEI's recommendations have been endorsed by many organizations, including the US National Endowment for the Humanities, the UK's Arts and Humanities Research Board, the Modern Language Association, the European Union's Expert Advisory Group for Language Engineering Standards, and many other agencies around the world that fund or promote digital library and electronic text projects. Recognizing its importance in the emerging digital library community, the Library of Congress has produced guidelines for best practice in applying the TEI metadata recommendations for interoperability with other standards.