:This paper discusses a computer modeling system being developed by Springwater Micro Data Systems. The system, SIFEM, simulates normal and oblique, vehicle-to-vehicle side impacts. The system is being developed as a practical, user friendly, design and evaluation tool for the practicing design and test engineer.Side impact computer models most commonly used in the industry today generally fall into two main groups. One group involves overly simplified one and two dimensional spring-mass models to represent the vehicle and its occupants. The second group takes the other extreme, using advanced analytical methods to develop 3-dimensional linked mass and finite element models. These advanced models generally require large, expensive computing systems to operate. Both groups of models impose severe restrictions, limiting their usefulness as a practical design and test evaluation tool. The SIFEM system, discussed in this paper, is a compromise between these two modeling groups.