Adversus Haereses is the commonly used Latin title for a book by the Church Father Irenaeus, Bishop of Lyon in Gaul (now France).
It is also often cited as Against Heresies or On the Detection and Overthrow of the So-Called Gnosis.
It is a five-volume work against Gnosticism and other Christian heresies, written around 180 CE.
It is sometimes confused with: