This guide presents the most relevant aspects to take into account when developing a Bus Rapid Transit (BRT) project in cities of the developing world, specifically concentrating on Latin America, while providing examples of several of these systems. The document describes the different steps one must take into account in a BRT project and the relevant details of such a process. Special attention has been given to the challenges that decision makers confront when developing a BRT system and the elements and tools that are available to them in order to move forward with the implementation of a successful system.