The Acoustic ToolBox includes four acoustic models: BELLHOP: A beam/ray trace code KRAKEN: A normal mode code SCOOTER: A finite element FFP code SPARC: A time domain FFP code A common input structure has been used throughout so that only minor modifications are needed to switch from one program to another. All the models produce shade files which can be processed using a common set of plotting routines to plot transmission loss vs. range or vs. range and depth. These plotting routines are contained in the GLOBAL directory.