According to both Catholic and Anglican canon law, a cathedral chapter is a college of clerics (chapter) formed to advise a bishop and, in the case of a vacancy of the episcopal see in some countries, to govern the diocese during the vacancy. In the Roman Catholic Church their creation is the purview of the pope. They can be "numbered", in which case they are provided with a fixed "prebend", or "unnumbered", in which case the bishop indicates the number of canons according to the rents. These chapters are made up of canons and other officers, while in the Church of England chapters now include a number of lay appointees. In some Church of England cathedrals there are two such bodies, the lesser and greater chapters, which have different functions. The smaller body usually consists of the residentiary members and is included in the larger one.
Originally, it referred to a section of a monastic rule that was read out daily during the assembly of a group of canons or other clergy attached to a cathedral or collegiate church. Later it came to be applied to the group of clergy itself.