In popular music an arrangement is a setting of a piece of music, which may have been composed by the arranger or by someone else. Most commonly, this is a matter of providing instrumentation for the songwriter or composer's basic melody and harmony. It may add details omitted by the composer, or it may replace those originally given and be merely based on the original work.

In classical music an arrangement is a setting of any composition for a different medium other than the one in which it was created: for example, a piano piece may be arranged for full orchestra, or an orchestral composition may be arranged for solo piano. Often arrangement involves considerable reworking of the original material, in conformance with the resources of the final medium.

As with composition, the ready availability of sound recording equipment has changed the understanding of what arrangement means. At one stage, credit for an arrangement would only be given to a person who had produced a written musical score or written chart of some sort. More recently, any original treatment of an existing work that is available for repeated performance by other players may qualify to be loosely called an arrangement. An unscored arrangement may be called a head chart (it is in the head of the musician(s)). Every time a piece of music is performed it has an arrangement, which may or may not have been done by a professional arranger.

An arrangement may specify or vary some or all of:

• Harmonies, including parts .
• Instrumentation.
• Style, dynamics and other instructions to the players.
• Sequence, including the order and number of repeats of sections such as verses and choruses, and provision of sections to be improvised by instrumentalists.
• Introduction, coda, modulations and other variations.

An arrangement is often an adaptation of a previously arranged piece of music for a musical application other than that for which it was originally meant. This includes arrangements for different instruments, for example an arrangement for piano or flute, or a duet, based on a symphonic piece, or an arrangement of instrumental accompaniment for vocal music). Or, it may be an adaptation for another musical style, for example adaptation of a classical piece for a jazz or rock ensemble, orchestration of a song written by a popular band, or an a capella setting of a song from a stage musical or an opera.

See also

• List of arrangers

Further reading

• The Billboard Book of Rock Arranging by Mark Michaels, ISBN 0823075370.