Preventing work-related violence (PREWVI) is a participatory action research project that aims to develop and implement an employee-driven intervention in mental healthcare. A pilot project was established at Lovisenberg hospital March 2021. Data on work-environment, employee health, work-related violence and utilization of preventive tools were collected from 360 clinical employees working in one of seven wards (response rate 74 %) and were used to develop ward-specific action plans for workplace improvement. To evaluate implementation of action plans and effects on improved work-environment, increased use of preventive tools and reduced levels of violence against staff, we used a mixed methods approach (focus group interviews and survey-questionnaires one year after baseline measures). Both qualitative and quantitative results from the pilot project will be presented at the conference.