The Human Vehicle Environment (HVE) program, developed by Engineering Dynamics Corporation, combines the vehicle parameters, physics and graphics into a single computer system for use in analyzing motor vehicle collisions, handling issues, studying occupant motion, etc. One of the most valuable assets of the HVE program is the open architecture that allows easy access to the data and graphics capabilities from an independent computer program. Thus, virtually any program that can be recompiled on the Silicon Graphics system can be set up to utilize the HVE tools. HVE is written in two computer languages known as C and C++ pronounced (“C plus plus”), this aids in the graphics processing. Unfortunately, FORTRAN programs do not automatically interface with C or C++ programs. These programs must be modified to allow a two-way data path to and from HVE. This paper will briefly review the concepts of interfacing programs and then give specific examples of combining FORTRAN programs with the HVE environment.