Abstract
This paper compares across six nations the mental health systems available to prisoners with the highest acuity of psychosis and risk combined with the lowest level of insight into the need for treatment. Variations were observed within and between nations. Findings highlight the likely impact of factors such as mental health legislation and the prison mental health workforce on a nation's ability to deliver timely and effective treatment close to home for prisoners who lack capacity to consent to treatment for their severe mental illness. The potential benefits of addressing the resulting inequalities are noted.