In the Caracas declaration of 1990, South American countries committed themselves to improve the human rights situation and social inclusion of people with mental disorders, de-institutionalise their care and develop community mental health services. There is however little evidence on the extent to which this has happened and what the current trends are. Indicators of institutionalised care include the provision of psychiatric hospital beds, forensic psychiatric beds, involuntary admission rates, supported housing, and residential homes. A particular question is how many people with mental disorders have been imprisoned, since the prison population increased substantially over the past decade (e.g. in Chile by more than 100%). The study has two aims 1) to assess indicators of institutionalised care for people with mental disorders across South America since 1990 and identify trends of de-, trans- or re-institutionalisation; 2) to establish the rate of people with mental disorders in a prison population in Chile. Primary data sources from ministries and social welfare, national prison administrations, hospital administrations and non-governmental organisations will be used to obtain indicators of institutionalised care. The prevalence of mental disorders in a prison population in Chile will be assessed in interviews of a representative sample of 800 prisoners. It is hypothesized that there is a trend towards trans-institutionalisation with a decrease of conventional hospital beds, but with high rates of people with mental disorders in prison and an increased provision of supported housing, whilst community services are still lacking. The findings will be explained against the background of societal, economic and professional developments in South America. The study will be based at the Universidad de Chile and the Queen Mary University of London, two centres of excellence in social psychiatry, and it will reinforce Europe’s leading position in Global Mental Health.