A prelude (German: Präludium or Vorspiel; Latin: praeludium; French: prélude; Italian: preludio) is a short piece of music, the form of which may vary from piece to piece. While, during the Baroque era, for example, it may have served as an introduction to succeeding movements of a work that were usually longer and more complex, it may also have been a stand-alone piece of work during the Romantic era. It generally features a small number of rhythmic and melodic motifs that recur through the piece. Stylistically, the prelude is improvisatory in nature. The term may also refer to an overture, particularly to those seen in an opera or an oratorio. A prelude and fugue generally consists of two movements in the same key for solo keyboard. In classical music, the combination of prelude and fugue is one with a long history. Many composers have written works of this kind. The use of this format is generally inspired by Johann Sebastian Bach's two books of preludes and fugues – The Well-Tempered Clavier – completed in 1722 and 1742 respectively. Bach, however, was not the first to compose such a set: Johann Caspar Ferdinand Fischer wrote a 20-key cycle in his 1702 work Ariadne musica. Many composers have written sets of 24 Preludes, such as Bach, Chopin, Scriabin, Shostakovich, and Debussy.

The following is a list of compositions by the Russian composer César Cui. Titles of overall works are supplied in English unless the non-Russian original is distinctive in some way. Russian titles are added where helpful and applicable. Years in parentheses refer to the composition dates, not publishing dates. Complete listings of individual numbers within a larger work are not given, although certain well-known or recorded selections are cited. For important selections within an opera, go to the Wikipedia article for that opera, listed below and on the Wikipedia category-page for Cui's operas. Many individual compositions by Cui (primarily songs and choral pieces) have been published over the years, especially in English and French editions, without information as to opus number, if any. In order to avoid inaccuracy and unnecessary clutter, only those pieces that verifiably do not belong to an opus are included below along with the works with established opus numbers. (Note: Cui's compositions, especially from the end of his life, remain in manuscript in the Russian National Library; likewise with the full orchestral scores of several of the operas. The recent publications of the last of Cui's instrumental works (Opp. 104–106) has addressed the research gap in his unknown works.)

The following is a list of compositions by the Russian composer César Cui. Titles of overall works are supplied in English unless the non-Russian original is distinctive in some way. Russian titles are added where helpful and applicable. Years in parentheses refer to the composition dates, not publishing dates. Complete listings of individual numbers within a larger work are not given, although certain well-known or recorded selections are cited. For important selections within an opera, go to the Wikipedia article for that opera, listed below and on the Wikipedia category-page for Cui's operas. Many individual compositions by Cui (primarily songs and choral pieces) have been published over the years, especially in English and French editions, without information as to opus number, if any. In order to avoid inaccuracy and unnecessary clutter, only those pieces that verifiably do not belong to an opus are included below along with the works with established opus numbers. (Note: Cui's compositions, especially from the end of his life, remain in manuscript in the Russian National Library; likewise with the full orchestral scores of several of the operas. The recent publications of the last of Cui's instrumental works (Opp. 104–106) has addressed the research gap in his unknown works.)