The master's thesis is a qualitative action research on the introduction of mental health advocacy in the social – care institution “Dom na Krasu”, which was in the process of transformation or deinstitutionalization at the time of the research. Our research focuses on eight individual cases we provided advocacy services to, and two advocacy campaigns focused on the wellbeing of all residents. Results show the situations of users before and after being included in the process, the advocacy process analyzed with the help of the concepts of advocacy, empowerment, sources of strength and obstacles that made the work easier or more difficult, and power structures in the total institution and their influence on advocacy efforts. The results together with the conclusions and the discussion outline the whole picture of the situations in which the users found themselves and the work we did with them. The main findings of the research show some practical advice for the implementation of advocacy actions, based on our good practices and our mistakes, while at the same time shedding light on the arbitrariness and problematic nature of the system, which allows an extremely easy curtailment of rights (imprisonment, conditioning of privileges, disregard of individual needs and will...) of people who live in institutions.