This work is a synchronic and diachronic study of phonological diversity in the Malay language of Jakarta, the capital of the Republic of Indonesia. Jakarta Malay is the native language of the majority of the inhabitants of Jakarta, whose population of over five million persons makes it the largest city in Indonesia and in Southeast Asia. Jakarta Malay is also acquired as a second language by many of the migrants who come to the metropolis from throughout Indonesia, and generally functions as the lingua franca of everyday discourse in the city. decade ago, a scholar writing about Jakarta began his discussion with this comment (Castles 1967:153): In the spate of studies about Indonesia since Independence, the phenomenon of Jakarta has been much noted but little investigated. The political drama enacted there is avidly studied, yet the people of the city remain less familiar than the Chinese of Semarang or the Javanese of Mojokuto.l Before World War II, when Jakarta was Batavia and Indonesia was the Netherlands East Indies, the capital city on the swampy northern coast of Java did not receive the same