Opus (Latin for "work", plural is "opera") is a term used to denote a piece or set of pieces. Usually, but certainly not always, the opus number indicates the chronological order of composition or publication. Beginning in the early 17th century, as composers began to publish sets of madrigals, instrumental sonatas, or other works printed, the publishers would often assign numbers to these sets so that they could be differentiated. The earliest application I'm aware of is the assignment of "Op. 1" to Heinrich Schütz's first set of 19 madrigals published in 1611, but there are almost certainly earlier instances.
Relying on opus numbers can be a problem for some composers. This is especially true for early composers (before the 1800s), and for composers who have not published many works. Let me give you some examples. In the 17th century, composers often went to different publishers in each country. These publishers might all assign different opus numbers to the same set of sonatas or concertos.
Some of Mozart's works were published, and thus bear opus numbers. One example is the three piano concertos #11-13, K. 413-415, composed in 1783 and published in Vienna as Op. 4. The sales of this set were successful enough for him to get his piano concerto #5, K. 175, composed in 1773, published the same year as Op. 7! Mozart's publications were rather spotty, so no one uses the opus numbers (see the next section).
A somewhat different situation exists with the composer Luigi Boccherini. Boccherini was a prolific and successful composer with many publications. Therefore most of his works carry a publisher's opus number, though these numbers may not reflect the actual composition order or chronology. However, Boccherini did keep his own chronological list of compositions to which he assigned his own opus numbers. Therefore, many of Boccherini's works carry two opus numbers. An example is his string quintet in C minor, G. 328, composed in 1780, was assigned Op. 31 #4 by Boccherini, but when it was published in 1813 it was assigned Op. 47 #10 by the publisher.
Over the past two centuries, scholarship into the works of specific composers has become more and more important as the historical significance of individual composers is studied and analyzed. Inevitably, as a scholar studies the output of a composer, a thorough and comprehensive works catalog becomes extremely useful. As these catalogs are compiled and included with biographical studies or used as a basis for the publication of critical editions of the scores, the numbering scheme used by the scholar occasionally comes into common usage. But why should these systematic numberings be necessary? As discussed above, opus numbers, though useful in some instances, are not always reliable or even meaningful, if they exist at all.
These works lists, or thematic catalogs, are somewhat familiar to even the most inexperienced classical music lover. Anyone who has seen a "BWV" number associated with a work by Bach, or a "K" number associated with a piece by Mozart has encountered one of these numbering systems. They are handy because they allow people to discuss these works using a shorthand method of reference. For instance, Bach wrote several preludes & fugues in C Major. There are no opus numbers for these pieces as Bach published few of his works. However, if someone mentions the prelude and fugue BWV 545, there is no ambiguity.
Another case is that of Boccherini mentioned in the preceding section. Using an opus number to refer to a given work by Boccherini is problematic at best. Therefore, the thematic catalog of Boccherini's works compiled by Yves Gérard and published in 1969 is often used in both scholarly works, and referenced in sound recordings. For the CD or record collector who endeavors to keep track of the works included in a growing collection, these works lists can provide an invaluable way of tracking specific compositions.
The following table briefly explains the abbreviations used on sound recordings to identify specific works. Sometimes the abbreviation reflects the name of the author; sometimes the name of the publication in which the works list appears. There are many more thematic catalogs than are represented here. The purpose of this list is not to show every thematic catalog, but rather to provide a quick reference to some of the most often used numbering systems. Additions or corrections are welcome.
A | Catalog of the works of Frantiek Xaver Duek (Dussek) by Vladimír Altner |
A | Descriptive Catalog of the works of Charles Tomlinson Griffes that do not have an opus number by Donna K. Anderson |
A | Thematic Catalog of the works of Richard Strauss by Erich Hermann Mueller von Asow (see AV) |
Al | Thematic Catalogue of the works of Jacques Offenbach by Antonio de Almeida |
AV | "Allroggen Verzeichnis" Catalog of the works of E.T.A. Hoffman by Gerhard Allroggen |
AV | "Asow Verzeichnis" Catalog of the works of Richard Strauss by Mueller von Asow |
AWV | "Auber-Werke-Verzeichnis" Catalog of the works of Daniel François Esprit Auber by Herbert Schneider |
B | Chronological Index of the works of Frédéric Chopin by Maurice J.E. Brown |
B | Catalog of the works of Antonín Dvořák by Jarmil Burghauser |
B | Catalog of the works of Philipp Heinrich Erlebach by Bernd Bäselt |
B | Catalog of the works of Leopold Hofmann by Allan Badley |
B | Catalog of the works of Joseph Martin Kraus by Bertil Herman van Boer, Jr. (see VB) |
B | Catalog of the works of Karl von Ordonez (Carlos d'Ordonez) by A. Peter Brown |
B | Catalog of the flute concertos of Johann Joachim Quantz Meike ten Brink |
B | Catalog of the violin sonatas of Giuseppe Tartini by Paul Brainard |
B | Catalog of the symphonies of Johann Baptist Vanhal by Paul R. Bryan |
B or Ben | Catalog of the works of Ignaz Joseph Pleyel by Rita Benton |
BB | Catalog of the works of Béla Bartók by László Somfai |
BeRI | Catalog of the works of Johann Helmich Roman by Ingmar Bengtsson |
BI | Catalog of the works of Frédéric François Chopin by Maurice J.E. Brown |
BL | Catalog of the works of Alessandro Rolla |
BR | Catalog of the works of the Bach Family part of the Bach-Repertorium at the Sächsische Akademie der Wissenschaften zu Leipzig |
BruWV | "Brunetti-Werke-Verzeichnis" Catalog of the works of Gaetano Brunetti by Olaf Krone |
BuxWV | "Buxtehude-Werke-Verzeichnis" Catalog of the works of Dietrich Buxtehude by Georg Karstadt |
BVN | Catalog of the works of Rued Langgaard by Bendt Viinholt Nielsen |
BWV | "Bach-Werke-Verzeichnis" Catalog of the works of Johann Sebastian Bach by Wolfgang Schmieder (sometimes designated by "S.") in Thematisch-systematisches Verzeichnis der Musikalischen Werke von Johann Sebastian Bach |
C | Catalog of the works of Johann Christian Bach |
C | Catalog of the works of Franz Ignaz Beck by Anneliese Callen |
C | Catalog of the works of Jan Ladislav Dussek by Howard A. Craw |
C | Catalog of the works of Giovanni Gabrieli by Richard Charteris |
C or Craw | Thematic Catalog of the works of Jan Ladislav Dussek by Howard Craw |
CNW | Catalogue of Carl Nielsen's Works by the Danish Centre for Music Publication |
CS | Cantiones sacrae - Collection of sacred songs by Thomas Tallis and William Byrd (1575) |
D | Catalog of the works of Franz Schubert by Otto Erich Deutsch |
D | Catalog of the violin concertos of Giuseppe Tartini by Minos Dounias |
DD | Catalog of the works of Béla Bartók by Denijs Dille |
deest | Derived from the Latin "deesse" meaning to be absent. May follow the catalog abbreviation to designate a work which does not appear in that particular catalog (ex. K. deest). Plural is "desunt" |
DF | Catalog of the works of Christoph Ernst Friedrich Weyse by Dan Fog |
DLR | "de Larrocha-Riva" Catalog of the piano works of Enrique Granados by Douglas Riva & Alicia de Larrocha |
E | Catalog of the works of Philipp Heinrich Erlebach by Diane Parr Walker & Paul Walker |
E | Catalog of the symphonies of Leopold Mozart by Cliff Eisen |
E or EvaM | Thematic Catalogue of his Instrumental and Orchestral Works of Josef Mysliveček by Angela Evans & Robert Dearling |
EG | "Grieg-Gesamt-Ausgabe" Catalog of the works of Edvard Grieg published by the Edvard Grieg Committee, based on the catalogs of Dan Fog, Finn Benestad & Dag Schjelderup-Ebbe |
F | Catalog of the works of Wilhelm Friedemann Bach by Martin Falck in Wilhelm Friedemann Bach: sein Leben und seine Werke (Kahnt 1919) |
F | Catalog of the trumpet works of Giuseppe Torelli by Martin Falck |
F | Catalog of the works of Antonio Vivaldi by Antonio Fanna |
F | Catalog of the works of Josef Myslivecek by Antonio Fanna |
FP | Catalog of the works of Francis Poulenc by Carl B. Schmidt in The Music of Francis Poulenc (1899-1963): A Catalogue |
FS | Catalog of the works of Carl Nielsen by Dan Fog & Torben Schousboe |
FVB | Fitzwilliam Virginal Book (c. 1562-1612) - Contains music by William Byrd, Giles Farnaby, John Bull, Orlando Gibbons, Peter Philips, William Inglott, Martin Peerson, Jan Pieterszoon Sweelinck, and others edited by W. Barclay Squire & J.A. Fuller Maitland |
FVK | Catalog of the wind music of Franz Vincenz Krommer (Frantiek Vincenc Kramář) without opus number as listed in The Wind Ensemble Catalog by Jon A. Gillaspie, Marshall Stoneham & David Lindsey Clark |
FWV | "Fasch-Werke-Verzeichnis" Catalog of the works of Johann Friedrich Fasch by Rüdiger Pfeiffer |
FWV | "Franck-Werke-Verzeichnis" Catalog of the works of César Franck by Wilhelm Mohr |
G | Catalog of the works of Luigi Boccherini by Yves Gérard |
G | Catalog of the works of Giuseppe Torelli by Franz Giegling |
G | Catalog of the violin concertos of Giovanni Battista Viotti by Remo Giazotto |
G | Catalog of the works of Joseph Bologne de Saint-George by Alain Guédé |
G | Catalog of 18th-Century Italian Works in Manuscript - Gimo |
Gia | Catalog of the works of Tomaso Albinoni by Remo Giazotto |
GP | Catalog of the works of Arnold Bax by Graham Parlett |
GWV | "Graupner-Werke-Verzeichnis" Catalog of the works of Christoph Graupner by Oswald Bill & Christoph Grosspietsch |
GraunWV | "Verzeichnis der Werke der Brüder Johann Gottlieb und Carl Heinrich Graun" Catalog of the works of Johann Gottlieb Graun and Carl Heinrich Graun by Christopher Henzel |
H | Catalog of the works of Carl Philipp Emanuel Bach by Eugene Helm |
H | "Verzeichnis der nicht in der Gesamtausgabe veröffentlichte Werke Ludwig van Beethovens" - Catalog of the unpublished works of Ludwig van Beethoven by Willy Hess (New Hess Catalog of Beethoven's Works by Green), compiled at the same time, but independently from, George Kinsky and Hans Halm (Das Werk Beethovens: thematisch-bibliographisches Verzeichnis seiner samtlichen vollendeten Kompositionen, Henle 1955). Used for works that Kinsky & Halm did not catalog. |
H | Catalogue of the works of Hector Berlioz by D. Kern Holoman in Berlioz published by Harvard University Press |
H | Thematic Catalog of the works of Frank Bridge by Paul Hindmarsh |
H | Catalog of the works of Marc-Antoine Charpentier by Hugh Wiley Hitchcock in his Les Oeuvres de Marc-Antoine Charpentier: Catalogue Raisonné (1982) |
H | Catalog of the works of John Field by Cecil Hopkinson |
H | Catalog of the works of Gustav Holst by Imogene Holst, daughter of composer |
H | Catalog of the works of Bohuslav Martinů by Harry Halbreich |
H | Chronological catalog of the works of Leo Sowerby by Ronald M. Huntington |
Hob | Catalog of the works of Franz Joseph Haydn by Anthony van Hoboken |
HV | "Herrman-Verzeichnis" Catalog of the works of Joseph Leopold Edler von Eybler by Hildegard Herrmann-Schneider |
HW | Catalog of the works of Johann Christoph Friedrich Bach by Hanssdieter Wohlforth |
HWV | "Handel-Werke-Verzeichnis" Catalog of the works of George Frideric Handel by Bernd Bäselt |
Hwv | "Heinichen-Werke-Verzeichnis" Catalog of the instrumental works of Johann David Heinichen by Günther Hausswald |
J | Catalog of the works of Piotr Ilyitch Tchaikovsky by Boris Jurgenson |
J | Catalog of the works of Carl Maria von Weber by Friedrich Wilhelm Jähns |
JC | Catalog of the works of Giovanni Battista Sammartini by Newell Jenkins & Bathia Churgin |
JSkat | "Tematický katalog skladeb" Thematic Catalog of the works of Josef Suk by Zdeněk Nouza and Miroslav Nový |
JW | Catalog of the works of Leo Janáček by Nigel Simeone, John Tyrrell and Alena Nemcová (Janáček's Works: a Catalogue of the Music and Writings of Leo Janáček, Oxford) |
K | Catalog of the sacred works of Gilles Binchois by Philip Kaye (The Sacred Music of Gilles Binchois, Oxford) |
K | Catalog of the works of Antonio Rosetti by Oskar Kaul |
K or Kk | Catalog of the keyboard works of Domenico Scarlatti by Ralph Kirkpatrick |
K or Kl | Catalog of the works of Oswald von Wolkenstein by Karl Kurt Klein |
K or Kr | Catalog of the works of Karl Ditters von Dittersdorf by Carl Krebs Kremsmünster |
K or KV | "Köchel-Verzeichnis" Catalog of the works of Wolfgang Mozart by Ludwig Ritter von Köchel |
Kn | Catalog of the works of Carl Friedrich Abel by Walter Knape |
KWV | "Kreutzer-Werke-Verzeichnis" Catalog of the works of Conradin Kreutzer |
L | Catalog of the works of George Whitefield Chadwick by Steven Ledbetter |
L | Catalog of the works of Claude Debussy by François Lesuré |
L | Catalog of the works of Franz Liszt by Peter Raabe |
L | Catalog of the keyboard works of Domenico Scarlatti by Alessandro Longo |
L or LA | Catalog of the works of Gaetano Brunetti by Germán Labrador López de Azcona in Gaetano Brunetti (1744-1798): catálogo crítico, temático y cronológico |
LWV | "Lully-Werke-Verzeichnis" Catalog of the works of Jean-Baptiste Lully by Max Schneider |
M | Catalog of the works of Ignaz von Beeke by F. Munter |
M | Catalog of the works of César Franck by Wilhelm Mohr |
M | Catalog of the works of Johann Gottlieb Graun and Carl Heinrich Graun by Carl Heinrich Mennicke |
M | Catalog of the works of Johann Adolph Hasse by Carl Heinrich Mennicke |
M | "Meta" Catalog of the works of Vagn Holmboe by Paul Rapoport |
M | Catalog of the works of Antonio Rosetti by Sterling E. Murray (Also see RWV) |
M | Catalog of the sonatas of Padre Antonio Soler by Frederick Marvin not cataloged by Rubio below (SR) |
M | Catalog of the works of Antonio Vivaldi by Gian Francesco Malipiero (same as R below) |
MH | Catalog of the works of Johann Michael Haydn by Charles H. Sherman and T. Donley Thomas in Johann Michael Haydn (1737-1806): a Chronological Thematic Catalogue of his Works (also see ST) |
MS | Catalog of the works of Johann Melchior Molter by Klaus Hafner |
MWV | "Molter-Werke-Verzeichnis" Catalog of the works of Johann Melchior Molter by Klaus Hafner |
NV | Catalog of the works of Sigismund Neukomm by Rudolph Angmüller in Werkverzisnis, Autobiographie, Beziehung zu seinen Zeitgenossen |
Op | Opus number, generally a chronological publication or composition number that may have been assigned by either the publisher or composer |
P | Catalog of the works of John Dowland by Diana Poulton |
P | Catalog of the works of Johann Michael Haydn by Lothar Herbert Perger in Thematisches Verzeichnis der Instrumentalwerke von M. Haydn |
P | Catalog of the works of Leopold Jan Antonín Kozeluh by Milan Potolka |
P or PadK or Padkrta | "Thematischer Katalog seiner musikalischen Werke" Catalog of the works of Franz Krommer (Frantiek Vincenc Kramár) by Karel Padrta |
P | Catalog of the works of Ottorino Respighi by Potito Pedarra |
P | Catalog of the works of Antonio Vivaldi by Mark Pincherle |
QV | "Quantz-Verzeichnis" Catalog of the works of Johann Joachim Quantz by Horst Augsbach |
R | Catalog of the works of Adelbert Gyrowetz by John A. Rice |
R | Catalog of the works of Gottlieb Muffat by Bartholomäus Riedl |
R | Catalog of the works of Antonio Vivaldi by Gian Francesco Malipiero as published by Ricordi |
RO | Catalog of the works of Louis Moreau Gottschalk by Robert Offergeld |
RV | "Ryom-Verzeichnis" Catalog of the works of Antonio Vivaldi by Peter Ryom |
RWV | "Rosetti-Werke-Verzeichnis" Catalog of the works of Antonio Rosetti by Sterling E. Murray (also see M.) |
S | Catalog of the works of Johann Sebastian Bach by Wolfgang Schmieder (see BWV above) |
S | Catalog of the works of Johann David Heinichen by Gustav Siebel |
S | Catalog of the unpublished works of Johann Nepomuk Hummel by Joel Sachs |
S | Catalog of the works of Franz Liszt by Humphrey Searle |
S | Catalog of the works of Leopold Sylvius Weiss by Douglas Alton Smith |
| Catalog of the keyboard music of Josef Antonín Stepan by Setkove |
Saf | Catalog of the works of Bohuslav Martinů by Milos Safranek |
SC or S-C | Catalog of the works of Leopold Sylvius Weiss by Douglas Alton Smith & Tim Crawford |
ScharWV | Catalog of the works of Franz Xaver Scharwenka by Matthias Schneider-Dominco |
SmWV | Das Musikalische Werk Franz Xaver Süssmayrs: Thematisches Werkverzeichnis Catalog of the works of Franz Xaver Süssmayr by Erich Duda |
Som | Catalog of the works of Johann Georg Albrechtsberger by Laszlo Somfai |
SR | Catalog of the works of Padre Antonio Soler by Padre Samuel Rubio in "Catálogo Crítico" |
ST | "Johann Michael Haydn (1737–1806): a Chronological Thematic Catalogue of his Works" by Charles H. Sherman and T. Donley Thomas (also see MH) |
SWV | "Schütz-Werke-Verzeichnis" Catalog of the works of Heinrich Schütz by Werner Bittinger |
SwWV | "Sweelinck Werke Verzeichnis" Catalog of the works of Jan Pieterszoon Sweelinck by Pieter Dirksen |
Sz | Catalog of the works of Béla Bartók by András Szőllősy |
T | Catalog of the works of Jean Sibelius by Ernst Tanzberger |
Terry | Catalog of the works of Johann Christian Bach by Charles Sanford Terry |
TFV or TrV | "Richard-Strauss-Werkverzeichnis" Catalog of the works of Richard Strauss by Franz Trenner |
TTK | "Tietz Tematiceskogo Kataloga" Catalog of the works of Anton Ferdinand Tietz by Natal'ja Valer'evna Gubkina |
TWV | "Telemann-Werke-Verzeichnis" Catalog of the works of Georg Phillip Telemann by Werner Menke & Martin Ruhnke |
VB | "Systematisch-thematisches Werkverzeichnis" Catalog of the works of Johann Kraus by Bertil Herman van Boer, Jr |
VB | "Valentini Bakfark Opera Omnia" Catalog of the works of Bálint Bakfark by Istvan Homolya and Daniel Benkö |
W | Catalog of the concertos of Johann Gottlieb Graun by Monika Willer in Die Konzertform der Brüder Carl Heinrich und Johann Gottlieb Graun (1995) |
W | Catalog of the works of Heitor Villa-Lôbos |
W | Catalog of the works of Johann Baptist Vanhal by Alexander Weinmann |
Wendt | Incipit Catalog of the trios of Johann Gottlieb Graun and Carl Heinrich Graun by Matthais Wendt in Die Trios der Brüder Carl Heinrich und Johann Gottlieb Graun (1983) |
WI | Catalog of the works of Giovanni Battista Viotti by Chappel White |
WKO | "Bibliographisch-thematisches Verzeichnis der Kompositionen" Catalog of the works of Carl Friedrich Abel by Walter Knape |
WoO | "Werk ohne Opuszahl" or "Work without opus number", typically unpublished works or works that were not assigned an opus number by the composer |
Wq | Catalog of the works of Carl Philipp Emanuel Bach by Alfred Wotquenne in Thematisches Verzeichnis der Werke von Carl Philipp Emanuel Bach |
Wq | Catalog of the works of Christoph Willibald Gluck by Alfred Wotquenne in Catalogue Thématique des uvres de Chr. W. v. Gluck (1904) |
WV | "Wagenseil-Verzeichnis" Catalog of the orchestral works of Georg Christoph Wagenseil by Helga Schölz-Michelitsch |
WV | Catalog of the works of Heinrich Scheidemann by Werner Breig |
WWV | "Wagner-Werke-Verzeichnis" Catalog of the works of Richard Wagner by John Deathridge, Martin Geck & Egon Voss |
Z | Catalog of the works of Luigi Boccherini by Benno Ziegler |
Z | Catalog of the works of Vaclav Pichl by Anita Zakin |
Z | Catalog of the works of Henry Purcell by Franklin J. Zimmerman |
ZWV | Catalog of the works of Jan Dismas Zelenka by Wolfgang Reiche in Jan Dismas Zelenka: Thematisch-systematisches Verzeichnis der musikalischen Werke |