This chapter provides the system dynamics model for control design in continuous and discrete time and space variables for traffic flow and also develops the basic framework for the control design. The problem is formulated as a feedback control design for the traffic as a distributed parameter system, i.e., in terms of Partial Differential Equations (PDE). DTR formulation for two alternate routes and then generalized for n routes is developed. Space discretization of the model results in Ordinary Differential Equation (ODE) representation, and its further time discretization produces difference equations. System dynamic equations for sample problems are developed, and a simple control law is also shown with computer simulation results.