We present a review of the Low Temperature Ion Source (LoTIS): its aims, design, performance data collected to date, and focused spot size projections when integrated with a FIB. LoTIS provides a Cs+ beam that has been measured to have high brightness (> 10 7 Am -2 sr -1 eV -1 ), and low-energy spread (< 0.5 eV). These source characteristics enable a prediction of subnm focused spot sizes. A FIB with the capabilities enabled by LoTIS would be well-suited to addressing FIB failure analysis tasks such as nanomachining, circuit edit, and site-specific SIMS.