Abstract
This chapter focuses on the problem of predicting passenger flows and levels of service on a given transit network that consists of a set of fixed lines. This is known as the transit-assignment problem (TAP), an important topic of public-transport-system analysis. Transit assignment models are widely used as important planning tools at strategic and operational levels, both in developed and developing countries. As such they are a critical block of multimodal network models of urban transportation systems. Important decisions concerning investments in public-transport infrastructure or services are normally supported by evaluation methodologies based on this sort of model.