Between the mid-eighteenth and mid-nineteenth centuries, Qing rulers, officials, and scholars fused diverse, fragmented perceptions of foreign territory into one integrated worldview. In the same period, a single "foreign" policy emerged as an alternative to the many localized "frontier" policies hitherto pursued on the coast, in Xinjiang, and in Tibet. By unraveling Chinese, Manchu, and British sources to reveal the information networks used by the Qing empire to gather intelligence about its emerging rival, British India, this book explores China's altered understanding of its place in a global context. Far from being hobbled by a Sinocentric worldview, Qing China's officials and scholars paid close attention to foreign affairs. To meet the growing British threat, they adapted institutional practices and geopolitical assumptions to coordinate a response across their maritime and inland borderlands. In time, the new and more active response to Western imperialism built on this foundation reshaped not only China's diplomacy but also the internal relationship between Beijing and its frontiers.