Legible London is a wayfinding system that aims to make London a world-class walking city. Applied Information Group proposed Legible London to Transport for London three years ago and installed a prototype in November 2007. The yellow book, which comes in two parts, was also developed to present the prototype system. The first is an overview of the background, research and development that culminated in the London pilot in the West End. The second is a visual summation that shows the applications, theories, concepts and findings that formn the foundations of the wayfinding system.