Criminal defendants today plead guilty in overwhelming numbers primarily because they perceive that this action is likely to lead to more lenient treatment than would follow conviction at trial. This view is probably justified because many studies have shown wide disparities between sentencing for those who plead guilty and those who go to trial. Despite the threat that plea bargaining may pose to constitutional values and its unfairness in terms of sentencing policy, advocates have articulated several penological rationales for extending special consideration to defendants who plead guilty. This paper takes issue with the argument that guilty pleas demonstrate remorse and suggests that defendants who refuse to plead guilty have been treated unfairly precisely because they were given a choice concerning the assessment of their sentences, and they made the wrong tactical decision. Also analyzed is the rationale that plea bargaining reduces government expenditures. Current approaches to plea bargaining tend to regard the process as a form of dispute resolution where the objective is not to determine the sentence that a defendant deserves but to make everybody happy. These supporters claim that plea bargaining gives defendants a more favorable option than they would have had in its absence, but they have not empirically investigated whether defendants truly benefit from plea bargaining in terms of convictions and outcomes. Moreover, plea bargaining often serves the personal and organizational interests of the lawyers and judges who administer it. Finally, the paper considers plea bargaining from a jurisprudential perspective, including the issue of contractual freedom, the concept of partial guilt which is inconsistent with the objectives of criminal law, and the risks of convicting the innocent. Many observers suggest that all these concerns are academic and that the overburdened courts have become so dependent on plea bargaining that prohibition cannot be contemplated however unjust it may seem. Discussions on lesser penological rationales for plea bargaining and the effect of plea bargaining prohibition on sentence severity are appended. The article contains over 200 footnotes.