In music, Op. 23 stands for Opus number 23. Compositions that are assigned this number include:
Barber – Medea Beethoven – Violin Sonata No. 4 Chopin – Ballade No. 1 Dvořák – Piano Quartet No. 1 Franck – Prélude, Aria et Final Gál – Das Lied der Nacht Grieg – Morning Mood Grieg – Peer Gynt Kabalevsky – Piano Concerto No. 2 MacDowell – Piano Concerto No. 2 Medea – Medea's Dance of Vengeance Myaskovsky – Symphony No. 6 Rachmaninoff – Preludes, Op. 23 Sarasate's Spanish Dances, Book III Schumann – Nachtstücke Scriabin – Piano Sonata No. 3 Sibelius – Songs for Mixed Chorus from the 1897 Promotional Cantata, song cycle for soloists and mixed choir (arranged 1898) Strauss – Macbeth Tchaikovsky – Piano Concerto No. 1 Widor – Surrexit a mortuis Wirén – Violin Concerto, for violin and orchestra (1946)