In 1662 the great sea-lord dynasty of the Cheng family expelled the Dutch from Taiwan, beginning a curious and little-known episode in cross-cultural diplomacy. China's new Manchu-Chinese Ch'ing dynasty and the greatest mercantile-colonial power of the seventeenth century negotiated with each other concerning conditions of trade and terms of military cooperation against their common enemy, the Cheng family. Conflicts between the two negotiating powers are seen as a great deal more than clashes between the Chinese tribute system of diplomacy and the Western "international system." The author's study suggests new perspectives on Chinese diplomatic tradition which may lead to a re-examination of foreign relations across cultural barriers.