Barry Cooper is an English musicologist, composer, and organist, known for his expertise in Beethoven's music. Cooper's contributions to Beethoven's music include his completion and realization of Beethoven's Symphony No. 10, based on the composer's sketchbooks. Cooper has also written extensively on Beethoven's sketchbooks, with his book Beethoven and the Creative Process being particularly notable. In addition to his work on Beethoven, Cooper discovered rare 17th-century French harpsichord music and is also an expert in music theory in 18th-century England.