The conductus (plural: conducti) was a sacred Latin song in the Middle Ages, one whose poetry and music were newly composed. It is non-liturgical since its Latin lyric borrows little from previous chants. The conductus was northern French equivalent of the versus, which flourished in Aquitaine. It was originally found in the twelfth-century Aquitanian repertories. But major collections of conducti were preserved in Paris. The conductus typically includes one, two, or three voices. A small number of the conducti are for four voices. Stylistically, the conductus is a type of discant (i.e. note-against-note polyphony). Its form can be strophic or through-composed form. The genre flourished from the early twelfth century to the middle of thirteenth century. It was one of the principal types of vocal composition of the ars antiqua period of medieval music history.

The conductus was most likely sung while the lectionary was carried from its place of safekeeping to the place from which it was to be read. But the origins of the term "conductus" remain obscure. The noun is derived from the verb conducere, which can mean to lead, guide, or escort. Thus according to one hypothesis, the genre was called "conductus" because it served to accompany a procession. For example, according to the record of manuscript in the Institución Colombina, Seville, the conductus Salve festa dies was used for the same role of procession as the ancient hymn. The hymn with the same name was sung during the procession to the altar. But conducere can also mean "to bring together" or "join together." Thus according to another hypothesis, the genre was called "conductus" because it brings sequence or hymn together. The conductus is based on a condensed version of a sequence or hymn. For instance, the conductus Orienti oriens is derived from the sequence Noster cetus iste letus.

The genre of the conductus most likely originated in the south of France around 1150 and reached its peak development during the activity of the Notre Dame School in the early thirteenth century. The conductus is the northern counterpart of the versus. In some sources, the versus and conductus can be interchangeably used, since both of them are strophic and accentual Latin poems. However, the conductus might be different from Aquitanian versus due to its inclusion of a caudae at the end. The melismatic flourish (caudae) in the conductus can separate the text out and disrupt the overall structure while Aquitanian melismas keeps the flow going.

Much of the surviving repertoire is contained in the Florence Manuscript and also the manuscript Wolfenbüttel 1099. In early documents, the conductus was often called "Benedicamus trope" or "benedictio." The early conducti are simple and free from the section of melismatic flourishes known as caudae. Caudae appear more often in conducti composed after 1200. Most conducti in the large thirteenth-century manuscript collections from Notre Dame are for two or three voices.

Many but not all conducti are anonymous. Some are attributed to some well-known poets and musicians of the time, such as Philip the Chancellor, Walter of Châtillon, Bernard of Clairvaux, Peter of Blois, and Perotinus. For instance, the text of the conductus Beata viscera was written by Philip the Chacellor and its music was attributed to Perotinus.

Common subjects of the poems are the lives of the saints, feasts of the Lord, the Nativity, as well as more current subjects such as exemplary behavior of contemporary witnesses to the faith, such as Thomas Becket. Some conducti from later period consist of songs which criticize abuses by the clergy, including some that are quite outraged. Other conducti refer to significant historical events. Philip the Chancellor's composition, Aurelianis civitas is associated with a student riot of 1200 in a French city, Orléans. In the poem, Philip lamented the conflict and its fatal consequences.

The conductus can include either one voice or multiple voices, known as monophonic and polyphonic compositions. The surviving repertories indicates the monophonic conducti are about double sizes of the polyphony type. But it was the polyphonic conductus that become one of principal musical genres in Parisian polyphony. Some melodies form monophonic compositions provide the basis for the multiple-voice writing.

The composition can be either in strophic or through-composed form. Unlike the motet, the conductus is not "based on pre-existing material." The composer invented the overall structure. In strophic form, the structure of each stanza is the same. In through-composed form, each stanza does not repeat. The strophic composition is typical in the earlier works. The through-composed composition came after 1200.