On the initiative of the American Bible Society (with the participation of the Scottish and Wurttembergian Bible Societies, and later of the Netherlands and British Bible Societies), a committee of experts was formed in 1955 to prepare for the publication of a new edition of the Greek New Testament. Its members were Kurt Aland, Matthew Black, Bruce Metzger, and Allen Wikgren. The new edition was to be specially oriented towards the needs of biblical translators. Accordingly, the 1st Edition of the Greek New Testament (1966) offered in its apparatus only variant readings for passages that were particularly uncertain or were highly important for the purposes of translation and exegesis. The new edition provided translators with a clear and convenient means, using the alphabetical letters AD, of grading each variant included in the Greek text as to the editors certainty of its authenticity. In addition to the text-critical apparatus, the editors included a punctuation apparatus that laid out differences in punctuation relevant to the sense of the text in the various Greek editions and in significant modern translations. The principal text included a number of deviations from the text provided in the Nestle-Aland up to the 25th Edition.