A parliamentary delegation (or congressional delegation, also CODEL or codel, in the United States) is an official visit abroad taken by a member or members of a legislature.
To schedule a parliamentary delegation, a member has to apply to the relevant committee chair, who then writes to the appropriate agency requesting funds and support for the trip. Various parliaments and legislatures maintain formal or informal groupings, such as congressional caucuses and all-party parliamentary groups, which maintain regular delegations to and from select countries; the European Parliament also maintains a formal delegation system for regular meetings with national and multinational parliaments.
Parliamentary delegations occur for solidarity, negotiative, research and investigation purposes, but are sometimes the source of controversy and criticism, when seen as junkets.
A congressional delegation abroad is not the same as the congressional delegation of a state (or a legislative delegation from a county to a state legislature), which is the entire body of current members elected to both houses of Congress from a specific state.