In this chapter, the models of different transportation processes in a congested road network are considered. The first section is devoted to a signal control problem formulated as a bi-level optimization program. An analytical solution for a two-commodity linear road network offers a practical and illustrative result to be taken into consideration by decision-makers in this sphere. A new algorithm for OD-matrix estimation based on the dual traffic assignment problem is described in the second section. The third section is devoted to the problem of emission reduction. The approaches presented in this book are shown to be well-implemented for coping with such problems. The time-depended vehicle routing problem in a congested road network is considered in the last section.