PyroSim 2007 is a user interface for FDS 5 (updated from FDS 4). It can import FDS 4 and FDS 5 input files. It cannot be used to create input files for FDS 4 or run FDS 4 simulations. Users interested in FDS4 support can still use PyroSim 2006. This new version adds broader support for FDS and parallel execution.