The computer model was developed to facilitate an understanding of the cause and effect relationships in the jury system for the purpose of improving juror utilization. The model, called JURIS, uses systems dynamics techniques and employs DYNAMO as its simulation language. The JURIS model is a discontinuous system through which jurors move irregularly. Because of the jury system's irregular nature, several special functions of DYNAMO were developed. The model consists of several interconnected sectors varies with the time of day, the day of the week, and the availability of courtrooms. The model begins with the jury pool of unlimited size on the first day of court proceedings, and it determines whether a trial will occur in each of the courtrooms. It compares the probability of a trial in one courtroom at a certain time of a specific day. If a trial occurs, the model will determine the type of trial (i.e., civil, criminal, etc.). Jury selection then begins, and the required number of prospective jurors is assigned to await voir dire. Peremptory challenges and challenges for cause constitute the heart of jury selection. When the jury reaches the prescribed size, the unused jurors are either returned to the pool, sent directly to another courtroom's panel, or dismissed. The length of a particular trial is determined by another special model function. JURIS can be inexpensively adopted to accommodate any court system, can greatly reduce the waste and mismanagement aspects of juror utilization, and thus has significance for policy planning. Tables, 10 references, graphs, and flow charts are included.