The Händel-Werke-Verzeichnis (abbreviated as HWV) is the Catalogue of Handel's Works. It was published in three volumes (in German) by Bernd Baselt between 1978 and 1986, and lists every piece of music known to have been written by George Frideric Handel. The catalogue also includes the first few bars of each piece and large amounts of factual information including manuscript sources, early prints, photographs, spurious works, etc. The catalogue does not include the full scores of Handel's works (for the full scores, see Händel-Gesellschaft and Hallische Händel-Ausgabe).
The HWV thematic catalogue serves as the modern numbering system for Handel's compositions. For example, Handel's Messiah is numbered as HWV 56.  The HWV numbers range from 1 to 612, however they do not represent a global date-ordering of composition; i.e. HWV 1 is not Handel's first work, nor is HWV 612 his last. Instead, the HWV numbers group works into musical categories, and provide a good ordering of the date of composition within each category. The following table lists the categories and the HWV number ranges.
|43–45, 218||Incidental music|
|49, 72–76||Odes and masques|
|200, 201||Italian trios|
|202–210, 269–277, 284–286||Hymns|
|211–217, 219–227||Italian arias|
|226, 228||English songs|
|229||German church cantatas|
|230, 233, 234||Italian sacred cantatas|
|231, 232, 235–245, 269–274, 276, 277||Latin church music|
|336–345, 347–356, 413||Orchestral works|
|357–379, 406–409, 412, 419–421||Solo sonatas|
|346, 410, 411, 414–418, 422–424||Wind ensemble works|
|A1, A3, A4, A6–A9, A10, A12||Arrangements by other composers|
There are gaps and anomalies in the HWV numbering system, so the above table is only useful as a guide (see the List of compositions by George Frideric Handel for more details).
The HWV numbers do not imply that Handel wrote exactly 612 works. The combination of unnumbered works, lost works, misattributed works, spurious works, variants (e.g. HWV 251 a–d), grouped works (e.g. HWV 229 1–7), and arrangements (e.g. HWV 482 1–4), all render meaningless the determination of the exact number of Handel's compositions.