A discrete-time adaptive control approach for uncertain linear multivariable networked systems is proposed. It is capable of dealing with unknown time-delays introduced by a communication network between plant and controller. Based on the idea of model reference adaptive control, two adaptive laws are presented to reduce the conservativeness that is usually introduced when the time-delays are unknown. The stability of the closed loop system is proven. Simulation examples provide a comparison of the proposed techniques to a non-adaptive algorithm.