The juvenile justice system in the U.S. is going throught a radical change. Some practitioners fear that the recent movement toward determinate sentencing philosophy for juvenile offenders is tantamount to abandoning a humanistic service orientation associated with 'individualized' justice. Yet U.S. practices have shown a serious misapplication of scarce correctional resources. Contributing to sentencing abuses (inappropriate placements and longer imprisonments of status offenders than youth with histories of violent behavior), the individualized justice mode has led criminal justice personnel to seek alternatives. A flexible determinate sentence model adapted from the U.S. parole system could counteract the abuses of discretionary authority. This model has a two factor matrix framework for determining mode of intervention and length of incarceration. The two dimensions of the guidelines are classification of offense severity and salient factor score (favorable outcome criteria, i.e., no further arrests). These guidelines are derived from local data by local policy makers. Continuous data collection permits modification of the guidelines to new information. The guidelines are flexible, allowing for alternative modes of intervention and limited duration of confinement. The new rational sentencing guidelines will prevent undue incarceration of the least serious offenders and redirect vital correctional resources to the nation's most troubled youth. Tables illustrate changes in juvenile justice legislation for several States from 1975 to 1978, salient factor scores, guidelines for decisionmaking, and proposed guidelines for decisionmaking for juvenile offender case disposition. Twenty-nine references are provided, together with examples of policies adopted in Washington and California. (Author abstract modified)