Firefighters (and other emergency responders) entering an unfamiliar building are at particular risk for getting lost, especially in the low-visibility situations present in fires. Helping them navigate and enable others to know where they are in 3D space would go a long way to improving safety. But the problem has proven to be a difficult one to solve. After tests of multiple candidates pretty much all failed, DHS, with help from WPI and Honeywell, developed GLANSER, Geospatial Location Accountability and Navigation System for Emergency Responders. But while GLANSER does work, there are some issues. Batteries are too big and heavy and it’s prohibitively expensive, out of the reach of many smaller fire departments. As an alternative, WPI has developed their own system, PPL, the Precision Personnel Locator. PPL is expected to be cheaper than GLANSER and have better battery life but WPI hasn’t yet found a manufacturer. In any case, greatly improved firefighter safety looks to be only a few years away.