As one of many fields of application, electronic monitoring (EM) of offenders can be used—in conjunction with other measures—for release preparation. Using such measures, policymakers expect an alleviation of the negative effects of imprisonment and the promotion of positive rehabilitative effects by adding structure and social support. At the same time, policymakers are willing to maintain community safety through the close supervision provided by EM. The present study examines participants’ psychological and psychosocial changes during two measures of electronically monitored release preparation, namely, home detention and early work release. These findings are compared with a randomized group of participants who remained in custody. In sum, we found no distinctive positive effects of the tested measures. Because most participants already displayed functional psychological characteristics at pretest, there was only a small margin for improvement through electronically monitored release preparation. We conclude that if rehabilitation is sought by the use of such measures, it is important to select a target group that is actually in need of rehabilitative support and equally important to conduct further research on the rehabilitative potential of EM measures.