The development and application of transit accessibility measures by geographic information system technology are described. The approach allows transit planners to focus on access to transit routes and bus stops at the neighborhood level and draws attention to the significance of the walk access mode to transit. Then land use, population, and employment characteristics are incorporated into the evaluation of transit service. A case study example of a “what-if” scenario for evaluation of transit service alternatives is discussed. Conclusions are offered about the use and further development of the approach for transit planners.