Congress enacted the Sentencing Reform Act of 1984 which created the mechanisms for replacing indeterminate sentencing with a more structured determinate sentencing system. Critics of the sentencing guidelines drafted by the Sentencing Commission established by the act have predicted that the guidelines would not fully address the problem of disparity and that they would interfere with plea bargaining and would increase the severity of prison sentences, thereby contributing to prison overcrowding. In testing the validity of these criticisms, this article examines the directives of the act and the guidelines. It then provides a statistical analysis of sentences issued prior to and since the guidelines' enactment. An analysis of guidelines-departure case law determines whether the factors used to justify departures from the guidelines are furthering the act's goals. Overall, the study indicates that the guidelines are generally meeting their goal of reducing disparity without measurably affecting plea bargain rates. Disparity persists, however, on a more limited scale due to differing approaches to ambiguous guidelines provisions. To enhance uniformity, Congress or the Sentencing Commission should provide clear guidance on consideration of offender characteristics in sentencing and regarding proportionality determinations for guidelines departures. The guidelines have also exacerbated prison overcrowding. This problem may be addressed by repealing the mandatory minimum sentencing provisions and by increasing the use of prison alternatives. 192 footnotes