A Barrister (also known as Barrister-at-Law or Bar-at-Law) is a member of one of the two classes of lawyer found in many common law jurisdictions with split legal professions. Barristers specialize in courtroom advocacy, drafting legal pleadings, and giving expert legal opinions. They can be contrasted with solicitors – the other class of lawyer in split professions – who have more direct access to clients, and may do transactional-type legal work. Barristers are rarely hired by clients directly but instead are retained (or instructed) by solicitors to act on behalf of clients.

The historical difference between the two professions – and the only essential difference in England and Wales today – is that solicitors are attorneys, which means that they can act in the place of their client for legal purposes (as in signing contracts) and may conduct litigation on their behalf by making applications to the court, writing letters in litigation to the client's opponent, and so on. A barrister is not an attorney and is usually forbidden, either by law or professional rules or both, from "conducting" litigation. This means that, while the barrister speaks on the client's behalf in court, he or she can do so only when instructed by a solicitor or certain other qualified professional clients, such as patent agents.