Bus stops are a critical element in any transit system. The advent of Intelligent Transportation System (ITS) technologies in the area of transit has developed a need for transit agencies to keep an up-to-date inventory of bus stop data. Unfortunately, most transit agencies do not have a bus stop inventory that can adequately support Advanced Public Transportation System (APTS) applications, and many other transit agencies do not have an inventory at all. The design, development, and maintenance of a bus stop inventory that will support an array of available APTS applications is described in this paper. Procedures used in the development of the Metropolitan Atlanta Rapid Transit Authority bus stop inventory are highlighted. The lessons learned from MARTA s experience should be valuable to other transit agencies that are planning to or are in the process of implementing an APTS.