The discovery on the archeological site of the former cathedral group of Autun of the probable remains of the domus ecclesiae mentioned in the VIIth century led to an examination of the question of these structures with multiple functions and a study of their development, as they are very often at the origin of episcopal palaces, as it is clearly the case in Autun. It is moreover at Autun itself, in the bishop's palace, that this conference was held from November 26 to 28, 2009. The fourteen presentations joined together here, which concern European cases as well as those from the whole of the Mediterranean world, tend to define more fully the character of early episcopal residences in respect to buildings for worship, to comprehend their design and to follow their evolution. They also underline the difficulty of the interpretation of the textual and archaeological data, when they exist.