This chapter describes the relation of usul and melodic structure in several of the sakil pesrevs in the Ali Ufki and the Cantemir Collection. It provides information on Buhurizade Mustafa Itri fragment. Although only a fragment, comprising the serhane and part of the mulazime, pesrev offers suggestive information on Itri's techniques as a composer and his place within the development of Ottoman music in the seventeenth century. Based on Itri's work on the Cantemir Collection, the writer believed that the generation of Itri and Hafiz Post was crucial for the process that led to the modern system, although the music of their time was in some ways more linked to the seventeenth century than it was to the succeeding musical eras. Discounting for the moment the functioning Turkish classical repertoire as it has come down through oral transmission, and looking only at written collections.