20th Century sheet music

Copyright, and why the free version may not be legal where you are

Most countries protect a work for seventy years after the composer's death, but the term and the exceptions vary. A score legally hosted in one jurisdiction may be an infringing copy in another, and the large public-domain archives handle this by flagging works whose status differs by country.

Where we link a free source we pass on what that source states. It remains worth checking the flag on the archive itself before downloading, because the answer genuinely depends on where you are.

Notation you may not have met

Twentieth-century scores introduce notation that older repertoire does not use: quarter-tone accidentals, proportional and graphic notation where horizontal space represents time rather than beats, prepared-piano instructions, extended techniques for strings and winds, and aleatoric boxes to be repeated freely.

Composers usually explain their own conventions in a preface. That preface is part of the score, and skipping it is the commonest reason a modern piece looks unplayable.