This dissertation examines architectural exchange amidst connected civilizational networks—European, Islamic, Hindu—with the intent to appreciate the richness and extent of this phenomenon. Emphasis is placed on mobility—of people, ideas, materials, artisans—and the way this mobility powers the process of architectural exchange. The influence of Asian architecture and landscapes on European sites has received extensive scholarly attention. However, this dissertation examines the lesser known architectural interplay between Europe and West and South Asia during the eighteenth century. The cities of Istanbul, Lucknow and Aleppo—urban centres governed by Islamic rulers—are chosen as exemplars of a wider phenomenon of architectural exchange that was not exclusive to Europe. The aim of this dissertation, then, is to argue that architectural exchange is neither rare nor exceptional. To do so, this dissertation surveys and synthesises the findings of disparate studies that document architectural exchange—studies which often focus on specific buildings—to interpret the breadth and depth of this global phenomenon. This perspective is inspired by the scholarship of world systems theorists and scholars who privilege the phenomenon of travel, particularly Geoffrey Gunn, Eric Leed and Andre Gunder Frank, who have convincingly destabilised Eurocentric representations of world history, and encourage recognition of parallels and equivalencies between competing civilizations, as well as the central role travel plays in the formation of these changing cities and civilizations. This sheds light on the reciprocity of architectural exchange and the many instances whereby European techniques, themes or motifs were incorporated into Asian buildings or landscapes. This scholarship has also inspired the notion of a 'gateway city'—simultaneously a port, portal or even the Sublime Porte—which is used to conceptualise sites that were located amidst dynamic networks of cultural exchange. The 'gateway city' enhances the interpretation of architectural exchange and even enables understanding of the port-ability of architecture. Moreover, it enables understanding of architectural exchange occurring beyond, and independently of, Europe, either within the Islamic world or within local networks of exchange in West and South Asia. The contribution of this dissertation is to provide a dynamic and interconnected view of architecture in the selected cities in the eighteenth century, as well as challenging historical convictions about „decline‟ and stasis in this period of Ottoman and Mughal history.