A Serjeant-at-Law (SL), commonly known simply as a Serjeant, was a member of an order of barristers at the English and Irish Bar. The position of Serjeant-at-Law, or Sergeant-Counter, was centuries old; there are writs dating to 1300 which identify them as descended from figures in France before the Norman Conquest, thus the Serjeants are said to be the oldest formally created order in England. The order rose during the 16th century as a small, elite group of lawyers who took much of the work in the central common law courts.

A barrister is a type of lawyer in common law jurisdictions. Barristers mostly specialise in courtroom advocacy and litigation. Their tasks include arguing cases in courts and tribunals, drafting legal pleadings, researching the law and giving legal opinions.