Hysteresis nonlinearity is an inherent characteristic of PZT (Pb-Zr-Ti) materials. It decreases the performance of the control system and even results in limit cycle oscillations . In , a general hysteresis definition is given by using rate-independent memory effects. For the hysteresis system, the output of the system depends not only on the present input but also on the past input or memory. Rate-independent means that the input-output relationship is invariant with respect to the change in time scales. The basic idea to deal with the hysteresis is through a compensation using the inverse of a right hysteresis model. So, the challenge is the PZT hysteresis modeling. In this chapter, the PZT milliactuator discussed in Chapter 1 is considered. The hysteresis model due to the PZT elements will be identified and used to design the compensator, and the dynamic responses of the structure with the hysteresis effects removed will be measured and identified to design the controller.