On completion of his medical studies, he went to serve his traineeship in France, where, in addition to establishing a reputation as an excellent physician, he got to know Voltaire. Returning to England to practice his profession, he became a member of the Royal Society and wrote a number of important scientific treatises. In 1765 he made a journey to Italy, out of which came the Letters from Italy, describing the Customs and Manners of that Country. In the years 1765 and 1766. To which is annexed an Admonition to Gentlemen who pass the Alps, in their Tour through Italy (R. Cave, London 1766). The Letters were fiercely criticized by Baretti, resident in London at the time, who was offended by what he considered their indiscriminate rancor. In his letters, sent to various correspondents at home, Sharp cast a critical eye on the conditions of life in Italy, and in particular the bigotry and superstition rife in the Catholic world.