While Alciphron himself remains a mystery, the form and content of his work seem, at first sight, very well known: he is the author of a unique opus, a collection of letters, organised in four books. Indeed, all modern editions contain the same 123 letters, presented in the same order and divided into the same four thematic units (letters of fishermen, farmers, parasites and courtesans, respectively). However, no preserved manuscript comprises all known letters and their order strongly varies from one manuscript to the other. Therefore, the structure of this work cannot be taken for granted and it is necessary to examine how we read Alciphron’s Letters. In which form were these letters transmitted to us? Do we have hints for their original arrangement? In order to answer these questions, this paper investigates the organisation of Alciphron’s work, first in the printed tradition, and then in the manuscripts. The letter collection, as we read it today, is an editorial reconstruction based on Schepers’ editions; before him, previous editors strongly depended on the editio princeps (1499): to the two books of the Aldine, they simply added a third book, which was progressively extended by incorporating new letters and fragments. The various manuscript families show traces of a common order of the letters and of their organisation in different books.