In networked control systems, multiple components (e.g. plants, sensors and controllers) exchange information and cooperate to achieve a joint goal. Unlike traditional control problems, a networked control system does not assume perfect transmission of information among components. It has been noted that the quality of communication can affect the performance of a given controller or even the achievable performance for any controller. For instance, if no information can be transmitted from an unstable plant to the controller, then there exists no controller that can stabilize the plant. On the other hand, controllers designed while ignoring the communication constraint cannot provide good performance or even stability. Thus, the interaction between control and communication needs to be understood. The purpose of this thesis is to study the performance limitation posed by the communication constraint. In particular, some traditional control problems are revisited in the networked control framework and new results are obtained. First, by using a time-domain approach, a Bode-like integral formula is obtained for discrete-time linear periodic systems, which can be used to model medium access-constrained systems with periodic communication scheme and asynchronous systems. It is shown that the log integral of sensitivity (which characterizes the disturbance rejection performance) depends only on the open-loop dynamics and the communication scheme but not on the controller, which makes it a fundamental limitation. Then, the networked cooperative platoon of vehicles is studied where a string of vehicles aim to proceed along a given trajectory while keeping a constant distance between adjacent vehicles. It is assumed that each vehicle can control its position based on the spacing error with respect to the preceding vehicle in the string, as well as on coded information transmitted by the lead vehicle. By using an information-theoretic approach, a lower bound to the integral of the sensitivity function of spacing errors with respect to a stochastic disturbance acting on the lead vehicle is established. The derived bound depends on the open-loop poles and zeros of the vehicles' dynamics as well as on the quality of communication. The lower bound is shown to be tight for a specific communication scheme and controllers. Next, feedback stabilization for Bernoulli jump nonlinear systems is investigated. Bernoulli jump systems have gained importance in the modeling of networked control systems where the communication channel is assumed to be memoryless. By using a mode dependent scattering transformation, the controller design is applicable to the case when the plant and the controller are interconnected through a communication network that introduces constant time delays. Finally, we look into the problem of designing a controller that feedback passivates a discrete-time linear time-invariant system, when the state information is transmitted to the controller across a communication channel. A design method of static feedback passivating controllers is presented for an appropriate notion of stochastic passivity. The main result is a certainty equivalence principle: any state feedback controller that ensures closed-loop passivity using the exact state of the plant will also ensure closed-loop stochastic passivity using an estimate of the state provided by the decoder, under the assumption the estimation error is bounded in the second moment and a certain matrix is nonsingular. The result is extended to a class of nonlinear systems that is linear in the control input.