António Mendes Coutinho, master mason and architect active in the Portuguese dioceses of Lamego and Viseu in the mid-1700s, is considered to be a disciple of the Italian architect Nicolau Nasoni, who had worked in the region of Porto. Mendes Coutinho is related to the construction of numerous of the most important examples of baroque architecture in the region of Lamego and Viseu, and is frequently indicated as the author of those projects. However, several authors also highlight the hypothesis that some of these works may have another authors, yet unknown and later succeeded by Mendes Coutinho. A careful observation of the chronology, documentation and characteristics of the various works allows the supporting of this hypothesis, as explained through this brief essay.