Lord John Dyson was Master of the Rolls (President of the Court of Appeal of England and Wales and Head of Civil Justice) for four years until he retired in October 2016. He was a Justice of the Supreme Court of the United Kingdom from April 2010 until October 2012. He was a Lord Justice of the Court of Appeal of England and Wales from 2001 until 2010 (and Deputy Head of Civil Justice from 2003 until 2006), a judge of the High Court of England and Wales from 1993 until 2001 and the judge in charge of the Technology and Construction Court from 1998 until 2001. He was a Recorder from 1986 until 1993. Lord Dyson was called to the Bar by the Middle Temple in 1968 and was awarded a Harmsworth Scholarship. He was the Treasurer of the Inn in 2017.
Lord Dyson practiced in Keating Chambers from 1968 and was appointed QC in 1982. In 1986 he accepted an invitation by 39 Essex Chambers to become Head of Chambers, a position he held until 1993 when he was appointed to the High Court. At the Bar, whilst at Keating Chambers he practiced mainly (but not exclusively) in the field of construction law. At 39 Essex Chambers, he had a more diversified practice including in the field of general common law, commercial law and sports law. Lord Dyson acted in many high-profile cases. He also appeared as counsel in many arbitrations and was appointed as arbitrator on various occasions. In his long judicial career, he decided many cases across the whole range of civil law, including contract, construction and commercial law, general common law, international law, and public and human rights law. Many of his judgments are reported in the Law Reports and are frequently cited as precedents.