Of the journeys he undertook, the longest and most important was, no doubt, that to Paris in 1805.

On the occasion of this visit some of his compositions were performed, and when Chopin arrived there twenty-five years afterwards, Elsner was still remembered by Lesueur, who said: "Et que fait notre bon Elsner?
Racontez-moi de ses nouvelles." Elsner was a very productive composer: besides symphonies, quartets, cantatas, masses, an oratorio, &c., he composed twenty-seven Polish operas.

Many of these works were published, some in Warsaw, some in various German towns, some even in Paris.

But his activity as a teacher, conductor, and organiser was perhaps even more beneficial to the development of the musical art in Poland than that as a composer.

After founding and conducting several musical societies, he became in 1821 director of the then opened Conservatorium, at the head of which he continued to the end of its existence in 1830.