This study examines the outcomes of best available empirical research regarding the effectiveness of treatment programs implemented in secure corrections to prevent the recidivism of serious (violent and chronic) juvenile offenders (from 12 to 21 years old). In this review 30 experimental and quasi-experimental studies are analyzed, comparing 2831 juveniles in the treatment groups and 3002 youths for the control groups. The global effect size of these 30 studies in terms of standardized mean difference was d = 0.14 in favour of the treatment groups. This size effect, in terms of "r" coefficient reached the value of 0.07, of low magnitude. The cognitive-behavioral methods of treatment were the most effective in decreasing recidivism. These results report that the rehabilitation programs for serious offenders achieve to reduce the general recidivism in comparison with the control juveniles in approximately seven percent.