The thesis highlights the importance of prison labour during the incarceration for the rehabilitation of offenders both in professional as well as social aspects after their release from prison. It is based on empirical findings, which were obtained from interviews with delinquent persons both during their incarceration and after their release from prison. In addition to the aspect of work, other factors and circumstances as well as their relationships are included and evaluated in the analysis. Existing reintegration projects for prisoners are presented. In cooperation with the Justizvollzugsanstalt Bielefeld-Senne, North Rhine-Westphalia and on the base of findings perspectives for optimal rehabilitation of offenders are pointed out.