Planning is key to the effective implementation of new sentencing systems, and well-planned and executed sentencing innovations can alter the behavior of judges and sentencing outcomes. In practice, however, few sentencing policy changes are adequately planned and implemented. Sentencing policies are affected by judicial discretion and disparity, and the impact of various sentencing policy changes has not been sufficiently evaluated. In addition, tensions arise when sentencing policies direct judges to impose sentences that may be different from local notions of justice. Moreover, much of the literature on proportionality in punishment argues that punishment must be commensurate with the offender's relative blameworthiness. The experience of several countries in developing and implementing sentencing policies is discussed, and the author emphasizes the need for different jurisdictions to learn from each other's sentencing reform approaches. 42 references and 1 table