Incapacitation should be the primary basis for sentencing decisions. Research findings indicate that the amount of crime prevented by incarceration can be increased by lengthening the terms of those with high recidivism rates and shortening terms of those with low rates. Studies also have confirmed the belief that a common perception about the certainty and strength of a jurisdiction's sentencing policy promotes deterrence. Focusing on a specific group of offenders has an even greater deterrent effect, as in mandatory minimum sentence laws for crimes committed with firearms. While no prosecutor in a large urban center can cope with increasing caseloads without resorting to plea bargaining, it should be limited severely in serious cases of violent crime. Sentencing guidelines do not appear to promote deterrence and incapacitation policies, whereas mandatory minimum sentences and habitual offender statutes further these goals. But such reforms cannot be made in a vacuum, and States must consider the problem of prison overcrowding. While prosecutors' career criminal units have achieved phenomenal conviction rates and long sentences, they are not achieving their maximum incapacitation effect because they do not consider prior juvenile convictions as criteria for cases. Prosecutors are beginning to develop programs for the youthful violent recidivist, although rules regarding the use of juvenile conviction records impede such efforts. The article includes 16 footnotes.