Rationale:Automated Driving System (ADS)-equipped vehicles are becoming a reality in the market. The studies below suggest that road users prefer ADS-equipped vehicles to have additional signals to indicate when the vehicle’s ADS is engaged and to indicate the vehicle’s intended movement. National Highway Traffic Safety Administration’s (NHTSA’s) Federal Automated Vehicles Policy also supports the need for ADS-equipped vehicles to communicate with pedestrians and other road users to improve road users’ perceived safety and comfort level as ADS-equipped vehicles are introduced. Moreover, UNECE Working Party on Lighting and Signalling (GRE) has established a Task Force for Autonomous Vehicle Signalling Requirements (AVSR) to evaluate the need for ADS equipped vehicle to communicate with others.Additional lamps are a means of identifying ADS-equipped vehicles and communicating the ADS-equipped vehicle’s movement or intended movement. There are many lighting concepts and proposals for ADS-equipped vehicles within the U.S. and internationally. There is no standard today. It is important to create and establish a standard for ADS lamps that is harmonized and recognized internationally to avoid confusion and complexity.This Recommended Practice provides guidance in the development of a standardized lighting solution to meet these needs.