The 1983 Mental Health Act made a requirement under Section 58 for a second opinion by an Appointed Doctor when a detained patient either did not understand the nature, purpose, and likely effects of a treatment or did not consent. The present study is confined to second opinions relating to ECT (electric convulsion therapy) and extended medication. It was noted in the Mental Health Act Commission's Biennial report that requests for second opinions varied in numbers between different hospitals and psychiatric units. In 200 personal visits by the author a Treatment Plan by the Responsible Medical Officer (RMO), which is an indication of good practice in the operation of the Act, was written in the case notes in only 66 cases (33%) and then most often by a junior doctor. This finding has been reported generally. It seemed appropriate, therefore, to explore the opinions of Consultant Psychiatrists on the legal requirement for second opinion.