RET editions keep closely to the original physical book or manuscript. They retain the original spelling, including sometimes many archaic letters, contracted or curtailed forms, marks of abbreviation, and ligatured typeface. The editor's specific purposes dictate the degree to which the original character set is maintained. All RET editions record both the bibliographical text (title-page, table of contents, running titles, foliation and pagination, catchwords, signatures, and colophons) and the textual contents. Occasionally RET may produce critical editions, in which variant readings are recorded.

Each RET edition belongs to one corpus, English literature in the Renaissance. For this reason, the encoding of all texts follows guidelines. No claim is made for the superiority of these guidelines to other methods, except that they are informed by the characteristics of Renaissance texts. RET encodes all texts in SGML, the only international ISO standard for the exchange of electronic documents, and some also in the COCOA markup, employed in traditional text-analysis software and described in the TACT manual. The encodings differ in syntax, but the texts are identical in all other respects, and the information found only in the tags is similar. The Guidelines of the Text Encoding Initiative, which employ SGML, are an exceptionally useful tool for anyone encoding literary texts. SGML-encoded RET texts, for example, always have a TEI header and adopt many TEI entities and elements.

The principles of RET editions are as follows: