Beethoven's piano concertos (except for the fifth) were written initially for his own use, and were not published until after he had played them several times. This had two advantages - firstly he could prevent other pianists playing them, and thus preserve their novelty and interest; secondly, the fact that he had not written down the piano solo part in its final form did not matter - so all the early performances were probably quite different from one another! The fourth concerto was the first for which Beethoven had a new piano available; one with a greater compass. It reached the C three octaves above middle C, a fourth higher than before, and the piano writing exploits these upper registers frequently.

We are not certain when this concerto was first performed: there is some evidence that it was performed privately at the Vienna home of Beethoven's patron Prince Lobkowitz in 1807. We know for a fact, however, that it was included in a mammoth 4-hour concert of Beethoven's music given on 22nd December 1808, which also included the premieres of the fourth and fifth symphonies, the Choral Fantasy (for piano, orchestra and choir) and much else besides. The performances, under-rehearsed and given in a cold hall were, to say the least, variable. The Choral Fantasy fell apart altogether and had to be restarted, but the concerto was well received. One listener described "a new forte-piano concerto of monstrous difficulty, which Beethoven played astonishingly well at the fastest possible tempos".

To begin a classical concerto with the solo piano is unusual; even more unusual is the gentleness of it, as if we were eavesdropping on a private meditation. The orchestra then tries the same thought, in a totally different key, and decides something can be made of it - and the concerto is under way, as if by accident. The concerto is in the usual three movements; a substantial sonata form allegro, a short meditative slow movement, and a vigorous dance-like rondo to close. Within this normal overall shape, Beethoven brings a number of surprises:

• As well as the entry of the strings at the very beginning, there are other entries in unexpected keys - such as the second piano solo entry part way throtigh the first movement.
• The design of the slow movement is very unusual, alternating assertive string passages with soft, meditative piano entries, until the two become reconciled.
  
• The opening of the rondo is another off-key entry. The main theme starts in C major and slips sideways to the home key of G major after a few bars.

Despite these innovative strokes, the concerto as a whole has a rounded perfection that has made it a favourite of Beethoven's concertos.