The province of Kefe (Caffa) was one of the Ottoman frontier provinces and played an important role in the Ottoman relations with Moscow and Bakhchisaray. One duty of the governor of Kefe was to control the Crimean khan and inform the Ottoman central authorities about the situation in the Crimea. Azak (Azov) belonged to the province of Kefe and, as an important frontier fortress, enjoyed special rights and privileges. Kefe and Azak were transit points for Muscovite envoys and merchants on their way to Istanbul, and their governors typically acted as the ‘ears and eyes’ of the sultan in regard to Muscovy and the Don Cossacks. Based on primary sources, this article examines the correspondence of the governors of Kefe and Azak with Moscow and discusses their impact on the OttomanMuscovite relations. Special attention is devoted to the titulature used by the Ottoman provincial governors in their letters addressed to the tsar.