Cohen's analysis of data from the District of Columbia indicated that minimum 2-year terms imposed on all adult defendants convicted of robbery would result in an 8 percent reduction in robberies by adults, while increasing the total prison population by 7 percent. Convicted burglary defendants would also be prime candidates for incapacitation. Based solely on present and past criminal records, such a policy would be less susceptible to attack for reliance on controversial personal variables. Since sentencing policies would apply uniformly to groups of similar offenders, objections of unjust, unequal punishment would have less force. In contrast with this approach, collective incapacitation of all perpetrators of given offenses has only a modest impact on crime but can cause large increases in prison populations. Similarly, selective incapacitation strategies offer the possibility of achieving greater reductions in crime at considerably smaller costs in prison resources, but their success depends on the ability to identify high-rate offenders both early in their careers and prospectively. Tables and one figure are included.