Mendelssohn produced over 100 works in a wide variety of musical genres between the ages of 11 and 14. Perhaps the most impressive of these early works are the 12 Sinfonias for string orchestra. The works were performed - almost as soon as they were written - by members of the Prussian Court Orchestra at the Mendelssohn family home in Berlin in an informal series of Sunday morning concerts. The ensemble being directed by the young composer himself. This new urtext edition, by Boris von Haken, presents Mendelssohn's 12 Sinfonias in studyscore format in 2 volumes with preface, editorial and textual notes and 2 appendixes.