It is not known when Mozart completed his Concerto for Two Pianos and Orchestra in E-flat major, K. 365/316a, but research by Alan Tyson shows that cadenzas for the first and third movements are written in his and his father's handwriting on a type of paper used between August 1775 and January 1777.

[citation needed] However, most sources, including Tyson's book Mozart: Studies of the Autograph Scores[1] or more recently Lindeman's The Concerto: A Research and Information Guide (2006)[2] indicate that it was composed in 1779.

Also, the orchestra is rather more quiet than in Mozart's other piano concertos, leaving much of the music to the soloists.

The first movement is lyrical and "wonderfully spacious, as if Mozart is thoroughly enjoying himself and letting his ideas flow freely", as Ledbetter has noted.

[4] The middle movement is slow and refined; the orchestra stays in the background behind the pair of playful pianists.