This paper is a detailed examination of the historical development of New South Wales' mental health laws and of the Supreme Court's Protective Jurisdiction, written by a former Justice of the Supreme Court of NSW. Philip Powell AM QC covers the laws applicable in the young colony leading up to the consolidated and revised version of The Lunacy Act 1898 (NSW), which remained in force, with some amendments, until 1958. He argues that its replacement, The Mental Health Act 1958 (NSW) made only cosmetic changes until 1970 when the Office of the Protective Commissioner was created. Powell then covers changes in the law relating to mental health from 1982, when he began his term in the Protective Division of the Supreme Court of New South Wales, and his own activities in this respect. He examines the impact of the Guardianship Act 1987 (NSW) and the Mental Health Act 1990 (NSW) in detail. The concludes with a list of reported and unreported judgments of the Protective Division.