A mixedH2/H∞control problem is formulated and solved for tracking control systems. The control problem, which combinesH2andH∞performance criteria, can be applied to the design of compensators which achieve robust tracking performance in the presence of plant uncertainties. The optimal mixedH2/H∞tracking controller has a separation property similar to those of linear quadratic andH∞tracking controllers, and its solution consists of anH∞-optimal state feedback tracking control problem and an associated mixedH2/H∞-optimal estimation problem.