The existence of people with mental disorders in prisons is a reality found worldwide. The purpose of this article is not only to review the publications on this subject in 2009 but also to stimulate discussions that could contribute to its further scientific study.Most studies published in 2009 related to drug use among inmates and its consequences made it clear that this kind of disorder has a closer relationship with the crime than with mental illness.The existence of the mentally ill in prisons is a complex issue and the studies attempt to analyze aspects such as the type of disorder, sex of criminals, the opposition between incarceration and treatment, policy, harm reduction and stigma. A further study on the variables raised in this work is required, as well as examining others, to the extent that they are relevant to the various socio-economic and cultural realities.