A bar association is a professional association of lawyers as generally organized in countries following the Anglo-American types of jurisprudence. The word bar is derived from the old English/European custom of using a physical railing (bar) to separate the area in which court or legal profession business is done from the viewing area for the general public or students of the law.

Some bar associations are responsible for the regulation of the legal profession in their jurisdiction; others are professional organizations dedicated to serving their members; in many cases, they are both. In many Commonwealth jurisdictions, the bar association comprises lawyers who are qualified as barristers or advocates in particular, versus solicitors (see bar council). Membership in bar associations may be mandatory (necessary to practice law) or optional (voluntary) for practicing attorneys, depending on jurisdiction.

The use of the term bar to mean "the whole body of lawyers, the legal profession" comes ultimately from English custom. In the early 16th century, a railing divided the hall in the Inns of Court, with students occupying the body of the hall and readers or benchers on the other side. Students who officially became lawyers crossed the symbolic physical barrier and were "admitted to the bar". Later, this was popularly assumed to mean the wooden railing marking off the area around the judge's seat in a courtroom, where prisoners stood for arraignment and where a barrister stood to plead. In modern courtrooms, a railing may still be in place to enclose the space which is occupied by legal counsel as well as the criminal defendants and civil litigants who have business pending before the court.

In many Commonwealth jurisdictions, including in England and Wales, the "bar association" comprises lawyers who are qualified as barristers or advocates (collectively known as "the bar", or "members of the bar"), while the "law society" comprises solicitors. These bodies are sometimes mutually exclusive, while in other jurisdictions, the "bar" may refer to the entire community of persons engaged in the practice of law.

In Canada, one is called to the bar after undertaking a post-law-school training in a provincial law society program, and undergoing an apprenticeship or taking articles. Legal communities are called provincial law societies, except for Nova Scotia, where it is called the Nova Scotia Barristers' Society, and Quebec, where it is called the Barreau du Quebec.

The Canadian Bar Association (and its provincial and territorial branches) is a professional association of barristers, solicitors and advocates that serves the roles of advocates for the profession, provides continuing legal education and member benefits. It does not play a part in the regulation of the profession, however.

In India under the legal framework set established under the Advocates Act, 1961, a law graduate is required to be enrolled with the Bar Council of India. The process of enrollment is delegated by the Bar Council of India to the state Bar Councils wherein almost each state has a Bar Council of its own. Once enrolled with a State Bar Council, the law graduate is recognized as an Advocate provisionally for a period of two years, within which they must clear the All India Bar Examination (AIBE) conducted by the Bar Council of India. Once the advocate clears the AIBE test, they are entitled to appear and practice before any court of law in India.

There is no formal requirement for further membership of any Bar Association. However, Advocates do become members of various local or national bar associations for reasons of recognition and facilities which these associations offer. Some well-known Bar Associations in India include the Supreme Court Bar Association, Delhi High Court Bar Association, Bombay Bar Association, Delhi Bar Association, National Bar Association of India, All India Bar Association, etc.