A joint committee is a committee made up of members of both chambers of a bicameral legislature. In other contexts, it refers to a committee with members from more than one organization.
A joint committee (Gemeinsamer Ausschuss) comprises members of both Bundestag (two thirds) and Bundesrat (one third). It exists to ensure a working legislature during a state of defense.
A Joint Committee of the Irish Oireachtas (parliament) comprises members of both Dáil Éireann (the lower house) and Seanad Éireann (the upper house).
A joint committee of the Parliament of the United Kingdom is a select committee consisting of members of both the House of Commons and the House of Lords.
In the UK the term "joint committee" can also refer to a committee of local authorities established under the provisions of Local Government Act 1972.
A joint committee of the United States Congress is a congressional committee consisting of members of both houses and having jurisdiction over matters of joint interest. Most joint committees are standing committees (for example, the Joint Committee on the Library) but special joint committees have been created to address specific issues (such as the Joint Committee on the Conduct of the War). An example of a joint committee is the Joint Committee on the Library which consists of Senate and House of Representatives members.