CANTUS is a database of Latin ecclesiastical chant assembling indices of chants found in early sources for the liturgical Office, such as antiphonals and breviaries. It serves researchers in a variety of fields including ecclesiastical monody, the sacred polyphony of the Middle Ages and Renaissance, liturgical drama, hagiography, paleography, philology, ecclesiastical history and the history of monasticism, as well as performers of this early music (including church musicians and directors of liturgy) by providing a searchable database of detailed information for the over 370,000 chants entered to date. Researchers can, for example, generate a list of the manuscripts which contain a particular chant, identify manuscripts which record the Offices for particular saints or liturgical days, find chants by folio and item number in indexed sources, identify full texts, genres (such as hymn, antiphon, responsory, etc.), positions within the Office services, musical modes, concordances of particular chants in standard reference works, and perform numerous other queries. The CANTUS database was housed for over a decade at the University of Western Ontario with funding from the Social Sciences and Humanities Research Council of Canada.The new CANTUS website is intended to serve both users researching chant and database contributors.