Abstract: Prisons have a sole responsibility of rehabilitating and reintegrating offenders to the community. Despite going through the prisons, a great number of offenders still commit crime and are convicted again. The study aimed at assessing the ability of the drug and substance abuse treatment programs offered to inmates to address recidivism in prisons in Nairobi City County, Kenya. The study was guided by Reintegration theory and Cognitive behavior theory. A convergent parallel research design- Mixed method research approach was adopted. Six prisons with inmates serving up to 10 years were selected purposively, simple random sampling techniques was used to select 323 re- offenders, 36 leaders of the inmates were selected purposefully and 22 Key informants from prison administration and 4 probation officers selected purposively. The study used questionnaires, focus group discussion schedules and interview guides in data collection. Descriptive and inferential statistics were used to analyze quantitative data using SPSS version 25 and was presented by use of tables, Qualitative data was analyzed through thematic analysis and presented through verbatim. Study findings revealed that, drug and substance treatment programs are Positively correlated by (r= 083). The study recommends that, the government should ensure there is a proper mechanism for after release follows-up of the inmates to help them to avoid relapsing to drug use. The study recommended that, the government establishes a proper mechanism for after release follows-up of the inmates to help them to avoid relapsing to drug use. Further a comparative study on the effectiveness of prison rehabilitation approaches and probation should be conducted.

Keywords: Recidivism, Drug and Substance prevention, Offenders, Re-Offenders, rehabilitation approaches