TRB’s Transportation Research Record: Journal of the Transportation Research Board, No 2301 consists of 9 papers that explore motor vehicle speeds for urban sustainability; sight distance in the placement of concrete barriers on horizontal curves; neural network modeling of 85th percentile speed on two-lane rural highways; cross-section width and free-flow speed on two-lane rural highways; centerline and shoulder rumble strips on high-speed two-lane rural highways; safety and operating characteristics of Texas Super 2 highways; left-turn lane warrants for unsignalized intersections; impacts of converting two-way frontage roads to one-way operation; and capacity comparison of one-way and two-way signalized street networks.