Overhead luminaires often provide illumination on pavement, pavement markings, and nearby objects for nighttime drivers. Earlier studies have characterized the bidirectional reflectivity distribution functions of typical roadway surfaces. The luminaire spatial photometric beam distributions and relative spectral distributions have been investigated in part by the Illumination Engineering Society (IES). Mathematical models for luminance calculations are also established by the Commission Internationale de l'Eclairage (CIE; the International Commission on Illumination) and IES. Yet no computer models integrate such data to determine roadway luminance induced by overhead luminaires in conjunction with headlamp illumination for any given roadway geometry for the nighttime driver. Furthermore, existing models are limited to photopic vision, whereas nonphotopic (i.e., mesopic) vision prevails at night. With the Tarvip model being a suitable platform, work was undertaken under the sponsorship of FHWA to develop a computer model that would combine the available data and assess the performance characteristics of different overhead luminaires under different configurations and roadway characteristics for the nighttime driver. The model accommodates horizontal and vertical curves; custom luminaire configurations; and the CIE standard photopic, mesopic, and scotopic observers. With such a model, it is possible to analyze the visual benefits of existing or fictitious overhead luminaires under different configurations (i.e., different heights and gaps) on various roadway surfaces and geometries while oncoming vehicle glare is factored in without the need for field studies. The fixed overhead lighting module that was developed has been verified and validated in the field.