Prosecutors utilize several factors in determining whether to take a case to trial or to seek another disposition. First, evidence is evaluated on the basis of its complexity and difficulty in presentation. A street robbery case might be fairly simple, while an embezzlement case might require complex expert witness testimony. Second, evidence is evaluated for its relationship to constitutional questions such as police investigation and arrest procedures. A third area of question is the availability and reliability of witnesses. In cities with highly transient populations, witnesses might not be available to testify when needed, while witnesses with prior criminal histories or associations with the victim or defendant might be discredited at the trial. Finally, the circumstances surrounding the arrest are considered. Identification of defendants at the scene of the crime constitutes a stronger case than identification through a witness description. A stronger case is perceived if the suspect is arrested at the scene of the crime than if the arrest is made several days later. The results of a pilot survey in four cities showed that the prosecutors based their decisions on the following factors: constitutional problems, witness availability, and complaining witness problems. Nine references are included.