Traffic congestion is a growing problem in the world. It causes waste of time and fuel, increases pollution and stress. This is especially of road traffic in India, which faces problems like congestion, unpredictable travel time, urban chaos and noise. A smart traffic system automates the traffic control activity in order to obtain preference for the lanes on the basis of certain parameters. Hence, it provides an automatic control on the traffic in an optimized manner. It takes inputs from various sensors (utilising ultrasonic sensors, light sensors, motion sensors, cameras and IoT devices) and sends interrupt signals to the controlling devices. It consists of the IoT (Internet of Things) coupled with smartphone technology, RFID, sensors and a LADAR system. The system deals with the major issues of traffic congestion and collision avoidance and suggests remedies to tackle the same. In this chapter, various methodologies and architectures for smart traffic system operations are described.