This evaluation study on Gender Based Violence prevention services was conducted during February to May 2015, involving the marginalised populations in Arusha District Council. The purpose of the evaluation was to assess the progress of implementation of services to identify how services are integrated within Health Integrated Multi-sectoral (HIMS) programme to address gender equality. The programme was established in 2003 with main goal focused to promote gender equality to marginalised communities through mainstreaming thus contribute to poverty reduction. Gender Based Violence (GBV) is a worldwide public problem which cuts across all ages, classes, cultures and nationalities. The determinants occur at the individual, community and societal levels within all social, economic, religious and cultural groups. The evaluation employed both quantitative and qualitative as mixed methods for data collection. Tools used to collect data included semi-structured questionnaire, interview guide, document review, and observations. A non-probability purposive sampling was used to select GBV clients, TOTs, stakeholders and key informants. While the probability simple random technique was used to choose 35 out 45 participants for quantitative data. The approach was a formative process evaluation aimed to explore information on GBV preventive services provided and challenges encountered by the programme. The overall evaluation revealed that 30% participants were trainers (TOTs), 10% were programme staff, 20% stakeholders and 40% beneficiaries. The services provided included: training accounting to 17%, social services to vulnerable groups 46%, health care 29%, and other services 8%. However, the programme performance majority 45% ranked good. The qualitative revealed that awareness of GBV services are known to participants evidenced by testmonies. It was concluded that participants are aware of services provided by the programme and it has contributed in improving their social, economic and health status. Lastly, it is recommended that this programme has to be integrated into the district development plans for future sustainability.