This document reviews traffic regulation methods at highway intersections. It discusses different types of traffic control mechanisms used at intersections, including traffic signals, channelized intersections, and grade separated intersections. Traffic signals assign right of way using red and green lights to allow conflicting traffic streams to share the intersection. Channelized intersections separate turning movements from through movements to reduce conflicts and improve safety. Grade separated intersections eliminate conflicts by vertically separating crossing roadways with bridges or overpasses. The paper also reviews several past studies that have analyzed traffic flow at unsignalized intersections, developed models for estimating delays at roundabouts, and prioritized intersections for grade separation projects. Maintaining efficient traffic flow and reducing delays and accidents requires appropriate use of signals, channelization, and grade