The NGS2 instrument is an upgrade to the Adaptive Optics facility on the Gemini South telescope in Chile. This instrument uses the world's first multi region-of-interest EMCCD detector system to monitor 3 natural guide stars at rates up to 800 frames per second. Small changes in the position of the stars are measured and relayed to the adaptive optics control system, providing the input for correction of the tip and tilt component of atmospheric distortion. NGS2 will improve the sensitivity of the AO system and reduce acquisition time. This will improve the observing efficiency of the GSAOI instrument that was also built at RSAA.