The Bail Reform Act of 1984 allows a federal judge to detain an arrestee pending trial if the defendant constitutes a danger to other persons or to the community. This article examines the practical operation of the Act by reviewing statistical data from the United States Pretrial Services, the Administrative Office of the United States, a California State University study of the Eastern District of California, A General Accounting Office study of four judicial districts, and a Bureau of Justice Statistics study. Court impact studies of detention procedures at various jurisdictions on the federal and state level and problems in interpretation of the act are also analyzed. Results of the studies found that: (1) detentions are being ordered on a larger scale; (2) fewer cash bonds are being offered; (3) there is an increase in facilities, personnel, and expense to house defendants held pretrial; (4) detention requests vary widely by district; and (5) effectiveness of the Act as to increasing uniformity and predictability of bail setting as well as any increase in public safety is still unknown. Inconsistent interpretations of the Act result in the need to strengthen the legal standards for detention; provide a specific definition of "dangerousness"; eliminate or reduce broad categories of detainable offenses; establish who has the burden of proof in detention hearings; eliminate the rebuttable presumption where the defendant, in certain types of cases, is required to produce evidence of non-dangerousness; establish guidelines for maximum pretrial detention; and establish strict guidelines for the granting of cash bonds. Alternatives to pre-trial detention are offered, and an argument is made that the Bail Reform Act of 1984 offers benefits that outweigh its detriments, yet continuing legislative reform is essential. 206 footnotes.