Administratively, pretrial services officers are under the auspices of the Probation and Pretrial Services Division of the Administrative Office of the U.S. Courts and, by statute and hazardous duty retirement, are Federal law enforcement officers. When pretrial investigations are assigned to these officers, they must react quickly to obtain information on an arrested defendant, verify information obtained, and prepare a concise narrative report to the court in only a few hours. Obstacles that impede such investigations are identified in this article, and suggestions are offered for addressing them. Pretrial services officers must appear at bail hearings to answer questions about the pretrial investigations report. For defendants detained, the officers must continue to review and modify the reports and recommendations on those defendants who seek release through review or appeal of a detention order. For those defendants released, the officer should continue verification if necessary to monitor defendants' compliance with release conditions. In discussing the supervision of defendants on pretrial release, this article notes the statutory foundation for supervision, the management of defendants at risk of violating pretrial conditions, the supervision of defendants who are cooperating with the government in the prosecution of a case, and the importance of training. 54 notes