Diagnostic peritoneal lavage (DPL) is an emergency diagnostic procedure performed when intra-abdominal bleeding secondary to trauma is suspected. This procedure is part of the surgical skills section of the Advanced Trauma Life Support course. DPL is traditionally taught using anesthetized animals or cadavers. For reasons described below, these alternatives are not ideal. We have developed a computer-based diagnostic peritoneal lavage simulator. Our system addresses the shortcomings of the traditional method. We have used our system to teach ATLS. Preliminary results suggests that our system is effective.