This thesis takes into consideration the first vernacular translations of Galen's De methodo medendi. The first translation is found in London, British Library, Sloane MS 6, ff. 180v-203v: a surgical compendium translated for the most part from Latin, which contains both surgical and philosophical information. The English text of De methodo medendi comes from De ingenio sanitatis, the twelfth-century translation by Gerard of Cremona of the Arabic version of the treatise. The Greek text, taken from Johnston-Horsley's edition of 2011, has been compared with the Latin text found in an unpublished manuscript (London, Wellcome Library MS 287), and with the English text in manuscript Sloane 6. Another Middle English translation of De methodo medendi is found in the Questyonary of Cyrurgyens, a compilation published in 1533 in Montpellier and then translated and printed into English by Robert Copland in 1542. From the analysis of these translations it emerged that, despite the great number of practitioners with no training or qualification, the line that divided the literate and unlearned healers was not so clear as could be imagined or as many scholars stated. Undoubtedly many barbers, surgeons and apothecaries learned their art over a number of years of apprenticeship and without attending university courses, but at least part of surgeons' guild could read English and even some Latin, and sought to get the texts of the ancient medical authorities in order to climb the medical cursus honorum. Far from being illiterate, many of them knew some Latin and longed to learn some Greek words: a desire that clearly emerges in reading the translation of Galen's fourth book in the Questyonary of Cyrurgyens and especially in analysing the differences from the translation in manuscript Sloane 6. These differences show how English surgeons increasingly wanted to acquire Galen's original medical knowledge and medical vocabulary albeit anglicised, and they preferred this to Latin, which was used as a prerogative by literate physicians. Literate surgeons encouraged the copying of Galenic treatises in a learned vernacular anglicised language, as they wanted to obtain an easier access to them than that given by rare and unaffordable manuscripts. Their aim was to read at least some parts of the ancient medical works, and to improve their medical approach especially through Galen's method of medical practice, which they could find only in De methodo medendi.