The subject of this study is the office for the Feast of St. Vojtěch (St. Adalbert) and publication thereof, which is something that Czech musicology has lacked so far. Scholars have been able to identify this complete office in sources in the Czech Republic dating back as far as the mid-fourteenth century. The source situation and also the fact that this office includes a responsory taken from the office of St. Stanislaus (from the mid-thirteenth century) indicate that formation of the complete office for the Feast of St. Vojtěch was probably related to the rapidly-developing cult of St. Vojtěch during the period around 1300. However, the conception of this office differs greatly from that of canonical hours in general at that time, because its chants do not proceed by the modes and most of them have unrhymed texts. The office contains at least three chants certainly taken from offices of other saints, and on the other hand a group of chants that may be called original, which are musical settings of an unrhymed text from the legend of St. Vojtûch by Canaparius and are distinctive in their shared archaic recitative procedures. Thus in all probability the complete Czech office of St. Adalbert came into being during the period around 1300 as a compilation of older chants supplemented by several contemporary rhymed chants.