GeMS is the Gemini Multi-conjugate System. The system includes 5 Laser Guide Stars, 3 Natural Guide Stars, 3 Deformable Mirrors 1 Tip-Tilt Mirror. In this paper we focus on the control of the Tip-Tilt loop. Two new controllers have been implemented and tested, namely Kalman and H-infinity. We demonstrate that these controllers provide the means to efficiently attenuate vibration or certain frequency bands for GeMS. © 2011 Optical Society of America.