During large disasters, like hurricanes, wildfires and terrorist attacks, people want emergency responders to arrive quickly and help people deal with the crisis. In order to do their best, police, medics, firefighters and those who manage them need lots of information: Who is located where, needing what help? And what equipment and which rescuers are available to intervene? With all of the technology we have, it might seem that gathering and sharing lots of information would be pretty simple. But communicating through a disaster is much more challenging than it appears.