When Pompey conquered Syria-Palestine in 64–63 B.C., the Nabataeans remained outside Rome’s grasp. Although neighbors of the Hellenized world for some time, and in close contact with the Graeco-Roman cities of the Decapolis in the years leading up to A.D. 106, it was only after annexation that the Nabataeans officially came under the auspices of Roman control. When Trajan created from the Nabataean Kingdom around Petra the new Provincia Arabia (Arabia Petraea), life in the area was bound to change. Looking at the new provincial capital of Bostra, in southern Syria, and at Petra, the greatest Nabataean city, it is clear that alterations to the urban façades of the new province were made swiftly and continued to be made for some time. Monumental arches, Roman-style temples and public buildings, new roads, and a variety of civic spaces reshaped the urban hubs of the province. These overt expressions of Rome’s newfound ascendancy are clear enough; but what about less visible aspects of the urban fabric? What happened when no-one was watching, and the goal was not to send a message of Rome’s dominance, but rather to sustain life and facilitate its comforts in the best manner possible? Water systems in particular are an, if not the, essential part of every city’s underpinnings, and an absolute sine qua non for life in the Near East. With the exception of the Romans’ soaring, arched aqueducts, however, most water supply systems were unspectacular and relatively inconspicuous. This thesis examines such systems in three well-known centers of Nabataean and Roman life (Bostra, Petra, and Humayma), each belonging first to the Nabataean Kingdom and then the Province of Arabia, to determine the extent to which “Roman” methods of water-supply and management took root following the reconstitution of the area as a province. In some instances, it is clear that Roman engineering was imposed upon cities as new demands were placed upon civic water supply: Roman government officials, the military, and entrepreneurs demanded such comforts as baths and latrines. Yet in many instances, the Nabataean contribution to waterworks remained fundamental due to the efficiency and ingenuity of pre-existing systems. Far from living in a vacuum before annexation, the Nabataeans were well-acquainted with Graeco-Roman waterworks of the region, even baths, and had developed their own ingenious systems for collecting, transporting, and storing water to maximum effect. The “Romanization” of Nabataean water systems was in many ways inversely proportional to the overall “Hellenization” of these systems prior to Roman domination of Arabia. By looking at less overt aspects of material culture, particularly those not motivated by concerns of political and social domination, this work assesses more gradual processes of “Romanization.” In so doing, it becomes clear that the “Romans” inhabiting the cities and towns of the new province were not nearly as Roman as we might think, and the Nabataeans were hardly “provincial.” While the Roman presence in the area had a strong impact on waterworks of the second and third centuries A.D., the Nabataean underpinnings remained in most cities, and Nabataean hydrological engineering never fully disappeared, even well into later periods, continuing to affect water management habits in this region profoundly. Where Roman waterworks abounded, they did so to serve stable Roman populations, but even new inhabitants were not always enough to supplant former networks. At Humayma, we see signs of a different pattern of cultural interaction in stark contrast to “hybridization” and “Creolization.” This pattern is deemed “cultural parallelism,” a situation wherein Romans and Nabataeans lived beside one another with relatively separate facilities and maintained their own forms of hydraulic engineering. In addition to “cultural parallelism,” the present work looks at the many trajectories of cultural change in Nabataea and Roman Arabia through waterworks, opening a new data set for investigation and interpretation. This line of inquiry seeks to augment and breathe new life into stale concepts of Romanization which are overly-reliant on art historical concerns and often ignore the practicalities of urban infrastructure as useful means for assessing cultural change.