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This project summary report summarizes the research performed in Texas Department of Transportation (TxDOT) Project 0-5527. A low-profile barrier system was developed more than a decade ago for use in low-speed urban work zones with frequent cross-traffic entrances. However, there are many situations where speed limits transition from low speeds to high speeds or vice versa. In such situations, it would be very beneficial to derive the increased visibility benefits of the low-profile barrier in the low-speed areas. However, the low-profile barrier cannot now be used in such situations because there is no approved hardware that can connect the low-profile barrier to the taller traditional concrete median barriers. The purpose of this project was to develop a crashworthy transition barrier segment that can be used to connect the 20-inch-tall low-profile barrier to the 32-inch-tall F-shape portable concrete barrier. The transition barrier segment developed in this project is a reinforced concrete element that has a standard 32-inch-tall concrete barrier cross section at one end and a 20-inch-tall low-profile barrier cross section at the other end. The transformation from one barrier profile to another is accomplished using a series of planar surfaces. The transition barrier segment has an overall length of only 10 feet, which makes it easy to handle, transport, and set. Researchers performed two full-scale crash tests to evaluate the performance of the new transition barrier segment. The full-scale tests verified the performance of the new transition barrier segment.