The Book of Zambasta is Professor Bailey's name for a collection of Saka-Khotanese texts hitherto designated as E. The texts were first published in Berlin by E. and M. Leumann in the period 1933-6; and since then it has become possible to establish the meaning of almost the whole vocabulary used in the texts. The result is that Iranian scholars have a sound basis for their use of Saka linguistic materials. The prolexis is a close commentary on the establishment of the text. It contains all the evidence for the interpretation of words not previously understood. The words are arranged by the Brahmi syllabary and all but those which occur most frequently are given full references. Each word is placed within its linguistic matrix and is subjected to every semantic test before being allotted its final form and sense.