Abstract: The laser guide star facility (LGSF) is an integral component of thirty meter telescope (TMT), and is of critical importance in enabling TMT to achieve the performance required to meet the Science Requirements for high resolution imaging and spectroscopy. The LGSF is responsible for generating the artificial LGS required by narrow field infrared adaptive optics system (NFIRAOS) and by the next generation of the thirty meter telescope (TMT) AO systems. The following sections will discuss the LGSF's: design overview, LGSF asterisms, wavefront error budget and Laser Launch Telescope design.