This handbook is about mental health nursing and the law, focusing particularly on the Mental Capacity Act 2005 and the Mental Health Act 1983 (as amended in 2007). The Mental Capacity Act (MCA) is an entirely new piece of legislation and came into force in 2007. Additional mental capacity legal safeguards, the Deprivation of Liberty Safeguards (DoLS) came into force in 2009. The amendments to the Mental Health Act (MHA), which are both extensive and important, came into force in 2008. They affect people with mental illnesses and other mental health problems (including personality disorders and other psychological disorders), ‘organic’ conditions such as dementia, alcohol or substance misuse problems, learning disabilities, learning difficulties, developmental disabilities (e.g. autism), or combinations of those illnesses, disabilities and conditions. For any mental health nurse working in England or Wales in hospital settings, residential care, or the community, there have not been such significant changes in the law since the original Mental Health Act came into force in 1983.