Typically, public transit modeling requires the availability of an extensive data basis to enable detailed modeling, calibration, and validation. Sometimes such data is not available, even though there is demand for a simulation model to examine the impacts of planning decisions and strategies. However, available data may support a simulation model which, while not perfect, at least yields plausible results allowing the examination of broader impacts of planning decisions and strategies. In this paper a bus transit simulation model customtailored to manage on a scarce data basis is described. After an introduction to aims and scope, some background on bus transit systems, data availability, and related research is shared. Then a simulation model utilizing the available scarce data is proposed and the representation of the physical transit network, logical components, vehicle behavior, and transit provider's everyday operational management decisions are described. Finally, the outcomes of initial experiments on a small artificial transit network model are discussed, demonstrating the model's ability to yield plausible results.