As part of the U.S. FHWA-sponsored Detection Technology for IVHS program, ultrasonic, microwave radar, infrared laser radar, nonimaging passive infrared, video image processing with visible and infrared spectrum imagery, acoustic array, high sampling rate inductive loop, conventional inductive loop, microloop, and magnetometer detector technologies were evaluated at freeway and surface street arterial sties in three states. The states were selected to be representative of extremes in climatic conditions. The detector evaluation sites were located on roadways with high traffic density and suitable structures for mounting the overhead detectors. Approximately 5.9 GBytes of digital and analog vehicle detection and signature data and more than three hundred video tapes of the corresponding traffic flow were recorded. The detector outputs were time tagged and recorded on 88 MByte magnetic cartridges by using a data logger specifically designed and built for this project. Data analysis software was written to convert the data into an easily accessible Paradox database format compatible with a Windows personal computer operating system. Traffic volume ground truth data, obtained by counting vehicles from the recorded video imagery, were compared with the counts from the detector outputs. Speed ground truth data, obtained by driving probe vehicles through the field of view of the detectors and noting the vehicle speed as measured by the vehicle instrumentation, were compared with the speed measurement from the detectors. Several types of detectors were found to satisfy current traffic management functions. However, improved accuracies and new types of information may be required from detectors for future traffic management applications.