The purpose of this guide is to provide some elementary guidance to beginning traffic engineers in the NYCDOT Signal Timing Division on the standards of signal timing in NYC. The guide is intended to provide an understanding of the influence of traffic signal design on traffic operations, and is a primer on traffic signal timing, phasing, and coordination. The guide provides an introduction to the types of traffic signal designs available, but it cannot take the place of the extensive knowledge, field experience, and engineering judgement required to become proficient in signal timing design. Additionally, an introduction to alternative priorities in signal timing is covered, such as transit signal priority (TSP) and the use of real-time data for adjusting signal timing plans.